Convert.ToByte Convert.ToByte Convert.ToByte Convert.ToByte Method

定義

指定した値を 8 ビット符号なし整数に変換します。Converts a specified value to an 8-bit unsigned integer.

オーバーロード

ToByte(String) ToByte(String) ToByte(String) ToByte(String)

指定した数値の文字列形式を等価の 8 ビット符号なし整数に変換します。Converts the specified string representation of a number to an equivalent 8-bit unsigned integer.

ToByte(UInt16) ToByte(UInt16) ToByte(UInt16) ToByte(UInt16)

指定した 16 ビット符号なし整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 16-bit unsigned integer to an equivalent 8-bit unsigned integer.

ToByte(UInt32) ToByte(UInt32) ToByte(UInt32) ToByte(UInt32)

指定した 32 ビット符号なし整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 32-bit unsigned integer to an equivalent 8-bit unsigned integer.

ToByte(String, Int32) ToByte(String, Int32) ToByte(String, Int32) ToByte(String, Int32)

指定した基数での数値の文字列形式を、等価の 8 ビット符号なし整数に変換します。Converts the string representation of a number in a specified base to an equivalent 8-bit unsigned integer.

ToByte(Object, IFormatProvider) ToByte(Object, IFormatProvider) ToByte(Object, IFormatProvider) ToByte(Object, IFormatProvider)

指定したカルチャに固有の書式情報を使用して、指定したオブジェクトの値を 8 ビット符号なし整数に変換します。Converts the value of the specified object to an 8-bit unsigned integer, using the specified culture-specific formatting information.

ToByte(String, IFormatProvider) ToByte(String, IFormatProvider) ToByte(String, IFormatProvider) ToByte(String, IFormatProvider)

指定したカルチャに固有の書式情報を使用して、指定した数値の文字列形式を等価の 8 ビット符号なし整数に変換します。Converts the specified string representation of a number to an equivalent 8-bit unsigned integer, using specified culture-specific formatting information.

ToByte(Single) ToByte(Single) ToByte(Single) ToByte(Single)

指定した単精度浮動小数点数値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified single-precision floating-point number to an equivalent 8-bit unsigned integer.

ToByte(UInt64) ToByte(UInt64) ToByte(UInt64) ToByte(UInt64)

指定した 64 ビット符号なし整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 64-bit unsigned integer to an equivalent 8-bit unsigned integer.

ToByte(SByte) ToByte(SByte) ToByte(SByte) ToByte(SByte)

指定した 8 ビット符号付き整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 8-bit signed integer to an equivalent 8-bit unsigned integer.

ToByte(Double) ToByte(Double) ToByte(Double) ToByte(Double)

指定した倍精度浮動小数点数値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified double-precision floating-point number to an equivalent 8-bit unsigned integer.

ToByte(Int64) ToByte(Int64) ToByte(Int64) ToByte(Int64)

指定した 64 ビット符号付き整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 64-bit signed integer to an equivalent 8-bit unsigned integer.

ToByte(Byte) ToByte(Byte) ToByte(Byte) ToByte(Byte)

指定した 8 ビット符号なし整数が返されます。実際の変換は行われません。Returns the specified 8-bit unsigned integer; no actual conversion is performed.

ToByte(Char) ToByte(Char) ToByte(Char) ToByte(Char)

指定した Unicode 文字の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified Unicode character to the equivalent 8-bit unsigned integer.

ToByte(DateTime) ToByte(DateTime) ToByte(DateTime) ToByte(DateTime)

このメソッドを呼び出すと、必ず InvalidCastException がスローされます。Calling this method always throws InvalidCastException.

ToByte(Boolean) ToByte(Boolean) ToByte(Boolean) ToByte(Boolean)

指定したブール値を等価の 8 ビット符号なし整数に変換します。Converts the specified Boolean value to the equivalent 8-bit unsigned integer.

ToByte(Int16) ToByte(Int16) ToByte(Int16) ToByte(Int16)

指定した 16 ビット符号付き整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 16-bit signed integer to an equivalent 8-bit unsigned integer.

ToByte(Int32) ToByte(Int32) ToByte(Int32) ToByte(Int32)

指定した 32 ビット符号付き整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 32-bit signed integer to an equivalent 8-bit unsigned integer.

ToByte(Decimal) ToByte(Decimal) ToByte(Decimal) ToByte(Decimal)

指定した 10 進数値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified decimal number to an equivalent 8-bit unsigned integer.

ToByte(Object) ToByte(Object) ToByte(Object) ToByte(Object)

指定したオブジェクトの値を 8 ビット符号なし整数に変換します。Converts the value of the specified object to an 8-bit unsigned integer.

ToByte(String) ToByte(String) ToByte(String) ToByte(String)

指定した数値の文字列形式を等価の 8 ビット符号なし整数に変換します。Converts the specified string representation of a number to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(System::String ^ value);
public static byte ToByte (string value);
static member ToByte : string -> byte
Public Shared Function ToByte (value As String) As Byte

パラメーター

value
String String String String

変換する数値を含んだ文字列。A string that contains the number to convert.

戻り値

value と等価の 8 ビット符号なし整数。valuenull の場合は 0。An 8-bit unsigned integer that is equivalent to value, or zero if value is null.

例外

value は、オプションの符号とそれに続く数字 (0 ~ 9) のシーケンスで構成されていません。value does not consist of an optional sign followed by a sequence of digits (0 through 9).

valueMinValue 未満の数値か、MaxValue より大きい数値を表します。value represents a number that is less than MinValue or greater than MaxValue.

次の例では、文字列配列を定義し、各文字列Byteをに変換しようとします。The following example defines a string array and attempts to convert each string to a Byte. 文字列がnull 0 に解析されているString.Empty間、 FormatExceptionはをスローします。Note that while a null string parses to zero, String.Empty throws a FormatException. また、先頭と末尾のスペースが正常に解析されていても、通貨記号、桁区切り記号、小数点の区切り記号などの記号の書式設定が正しく行われないことに注意してください。Also note that while leading and trailing spaces parse successfully, formatting symbols, such as currency symbols, group separators, or decimal separators, do not.

using System;

public class Example
{
   public static void Main()
   {
      String[] values = { null, "", "0xC9", "C9", "101", "16.3", 
                          "$12", "$12.01", "-4", "1,032", "255",
                          "   16  " };
      foreach (var value in values) {
         try {
            byte number = Convert.ToByte(value);
            Console.WriteLine("'{0}' --> {1}", 
                              value == null ? "<null>" : value, number);
         }
         catch (FormatException) {
            Console.WriteLine("Bad Format: '{0}'", 
                              value == null ? "<null>" : value);
         }
         catch (OverflowException) {
            Console.WriteLine("OverflowException: '{0}'", value);
         }
      }
   }
}
// The example displays the following output:
//     '<null>' --> 0
//     Bad Format: ''
//     Bad Format: '0xC9'
//     Bad Format: 'C9'
//     '101' --> 101
//     Bad Format: '16.3'
//     Bad Format: '$12'
//     Bad Format: '$12.01'
//     OverflowException: '-4'
//     Bad Format: '1,032'
//     '255' --> 255
//     '   16  ' --> 16
Module Example
   Public Sub Main()
      Dim values() As String = { Nothing, "", "0xC9", "C9", "101", 
                                 "16.3", "$12", "$12.01", "-4", 
                                 "1,032", "255", "   16  " }
      For Each value In values
         Try 
            Dim number As Byte = Convert.ToByte(value)
            Console.WriteLine("'{0}' --> {1}", 
                              If(value Is Nothing, "<null>", value), number)
         Catch e As FormatException
            Console.WriteLine("Bad Format: '{0}'", 
                              If(value Is Nothing, "<null>", value))
         Catch e As OverflowException
            Console.WriteLine("OverflowException: '{0}'", value)
         End Try
      Next
   End Sub
End Module
' The example displays the following output:
'     '<null>' --> 0
'     Bad Format: ''
'     Bad Format: '0xC9'
'     Bad Format: 'C9'
'     '101' --> 101
'     Bad Format: '16.3'
'     Bad Format: '$12'
'     Bad Format: '$12.01'
'     OverflowException: '-4'
'     Bad Format: '1,032'
'     '255' --> 255
'     '   16  ' --> 16

注釈

メソッドを使用することは、 value Byte.Parse(String)メソッドに渡すことと同じです。 ToByte(String)Using the ToByte(String) method is equivalent to passing value to the Byte.Parse(String) method. value は、現在のスレッド カルチャの書式規則を使用して解釈されます。value is interpreted by using the formatting conventions of the current thread culture.

変換に失敗した場合に例外を処理したくない場合は、代わりにByte.TryParseメソッドを呼び出すことができます。If you prefer not to handle an exception if the conversion fails, you can call the Byte.TryParse method instead. 変換が成功Booleanしたか失敗したかを示す値を返します。It returns a Boolean value that indicates whether the conversion succeeded or failed.

こちらもご覧ください

ToByte(UInt16) ToByte(UInt16) ToByte(UInt16) ToByte(UInt16)

重要

この API は CLS 準拠ではありません。

指定した 16 ビット符号なし整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 16-bit unsigned integer to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(System::UInt16 value);
[System.CLSCompliant(false)]
public static byte ToByte (ushort value);
static member ToByte : uint16 -> byte
Public Shared Function ToByte (value As UShort) As Byte

パラメーター

value
UInt16 UInt16 UInt16 UInt16

変換する 16 ビット符号なし整数。The 16-bit unsigned integer to convert.

戻り値

value と等価の 8 ビット符号なし整数。An 8-bit unsigned integer that is equivalent to value.

例外

valueMaxValue より大きくなっています。value is greater than MaxValue.

次の例では、符号なし16ビット整数の配列Byteを値に変換します。The following example converts an array of unsigned 16-bit integers to Byte values.

ushort[] numbers = { UInt16.MinValue, 121, 340, UInt16.MaxValue };
byte result;
foreach (ushort number in numbers)
{
   try {
      result = Convert.ToByte(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", 
                        number.GetType().Name, number, 
                        result.GetType().Name, result);
   }                     
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", 
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//       Converted the UInt16 value 0 to the Byte value 0.
//       Converted the UInt16 value 121 to the Byte value 121.
//       The UInt16 value 340 is outside the range of the Byte type.
//       The UInt16 value 65535 is outside the range of the Byte type.
Dim numbers() As UShort = { UInt16.MinValue, 121, 340, UInt16.MaxValue }
Dim result As Byte
For Each number As UShort In numbers
   Try
      result = Convert.ToByte(number)
      Console.WriteLIne("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'       Converted the UInt16 value 0 to the Byte value 0.
'       Converted the UInt16 value 121 to the Byte value 121.
'       The UInt16 value 340 is outside the range of the Byte type.
'       The UInt16 value 65535 is outside the range of the Byte type.

ToByte(UInt32) ToByte(UInt32) ToByte(UInt32) ToByte(UInt32)

重要

この API は CLS 準拠ではありません。

指定した 32 ビット符号なし整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 32-bit unsigned integer to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(System::UInt32 value);
[System.CLSCompliant(false)]
public static byte ToByte (uint value);
static member ToByte : uint32 -> byte
Public Shared Function ToByte (value As UInteger) As Byte

パラメーター

value
UInt32 UInt32 UInt32 UInt32

変換する 32 ビット符号なし整数。The 32-bit unsigned integer to convert.

戻り値

value と等価の 8 ビット符号なし整数。An 8-bit unsigned integer that is equivalent to value.

例外

valueMaxValue より大きくなっています。value is greater than MaxValue.

次の例では、符号なし整数のByte配列を値に変換します。The following example converts an array of unsigned integers to Byte values.

uint[] numbers = { UInt32.MinValue, 121, 340, UInt32.MaxValue };
byte result;
foreach (uint number in numbers)
{
   try {
      result = Convert.ToByte(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", 
                        number.GetType().Name, number, 
                        result.GetType().Name, result);
   }                     
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", 
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//       Converted the UInt32 value 0 to the Byte value 0.
//       Converted the UInt32 value 121 to the Byte value 121.
//       The UInt32 value 340 is outside the range of the Byte type.
//       The UInt32 value 4294967295 is outside the range of the Byte type.
Dim numbers() As UInteger = { UInt32.MinValue, 121, 340, UInt32.MaxValue }
Dim result As Byte
For Each number As UInteger In numbers
   Try
      result = Convert.ToByte(number)
      Console.WriteLIne("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'       Converted the UInt32 value 0 to the Byte value 0.
'       Converted the UInt32 value 121 to the Byte value 121.
'       The UInt32 value 340 is outside the range of the Byte type.
'       The UInt32 value 4294967295 is outside the range of the Byte type.

ToByte(String, Int32) ToByte(String, Int32) ToByte(String, Int32) ToByte(String, Int32)

指定した基数での数値の文字列形式を、等価の 8 ビット符号なし整数に変換します。Converts the string representation of a number in a specified base to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(System::String ^ value, int fromBase);
public static byte ToByte (string value, int fromBase);
static member ToByte : string * int -> byte
Public Shared Function ToByte (value As String, fromBase As Integer) As Byte

パラメーター

value
String String String String

変換する数値を含んだ文字列。A string that contains the number to convert.

fromBase
Int32 Int32 Int32 Int32

value 内の数値の基数。これは 2、8、10、または 16 である必要があります。The base of the number in value, which must be 2, 8, 10, or 16.

戻り値

value の数値と等価の 8 ビット符号なし整数。valuenull の場合は 0 (ゼロ)。An 8-bit unsigned integer that is equivalent to the number in value, or 0 (zero) if value is null.

例外

fromBase が 2、8、10、16 のどれでもありません。fromBase is not 2, 8, 10, or 16.

- または --or- value は 10 進法でない符号なし数値を表しますが、前に負の符号が付いています。value, which represents a non-base 10 unsigned number, is prefixed with a negative sign.

value に、fromBase で指定された進法では使用できない数字である文字が含まれています。value contains a character that is not a valid digit in the base specified by fromBase. value 内の最初の文字が正しくない場合は、例外メッセージは、変換する数字がないことを示します。それ以外の場合は、このメッセージは、value に正しくない末尾文字が含まれていることを示します。The exception message indicates that there are no digits to convert if the first character in value is invalid; otherwise, the message indicates that value contains invalid trailing characters.

value は、10 進法の符号なし数値を表しますが、前に負の符号が付いています。value, which represents a base 10 unsigned number, is prefixed with a negative sign.

- または --or- valueMinValue 未満の数値か、MaxValue より大きい数値を表します。value represents a number that is less than MinValue or greater than MaxValue.

次の例では、さらに、バイナリ、8進数、10進数、および16進値の表現として文字列の配列を解釈しようとしています。The following example alternately attempts to interpret an array of strings as the representation of binary, octal, decimal, and hexadecimal values.

using System;

public class Example
{
   public static void Main()
   {
      int[] bases = { 2, 8, 10, 16 };
      string[] values = { "-1", "1", "08", "0F", "11" , "12", "30",                
                          "101", "255", "FF", "10000000", "80" };
      byte number;
      foreach (int numBase in bases)
      {
         Console.WriteLine("Base {0}:", numBase);
         foreach (string value in values)
         {
            try {
               number = Convert.ToByte(value, numBase);
               Console.WriteLine("   Converted '{0}' to {1}.", value, number);
            }   
            catch (FormatException) {
               Console.WriteLine("   '{0}' is not in the correct format for a base {1} byte value.", 
                                 value, numBase);
            }                     
            catch (OverflowException) {
               Console.WriteLine("   '{0}' is outside the range of the Byte type.", value);
            }   
            catch (ArgumentException) {
               Console.WriteLine("   '{0}' is invalid in base {1}.", value, numBase);
            }
         }                                 
      } 
   }
}
// The example displays the following output:
//    Base 2:
//       '-1' is invalid in base 2.
//       Converted '1' to 1.
//       '08' is not in the correct format for a base 2 conversion.
//       '0F' is not in the correct format for a base 2 conversion.
//       Converted '11' to 3.
//       '12' is not in the correct format for a base 2 conversion.
//       '30' is not in the correct format for a base 2 conversion.
//       Converted '101' to 5.
//       '255' is not in the correct format for a base 2 conversion.
//       'FF' is not in the correct format for a base 2 conversion.
//       Converted '10000000' to 128.
//       '80' is not in the correct format for a base 2 conversion.
//    Base 8:
//       '-1' is invalid in base 8.
//       Converted '1' to 1.
//       '08' is not in the correct format for a base 8 conversion.
//       '0F' is not in the correct format for a base 8 conversion.
//       Converted '11' to 9.
//       Converted '12' to 10.
//       Converted '30' to 24.
//       Converted '101' to 65.
//       Converted '255' to 173.
//       'FF' is not in the correct format for a base 8 conversion.
//       '10000000' is outside the range of the Byte type.
//       '80' is not in the correct format for a base 8 conversion.
//    Base 10:
//       '-1' is outside the range of the Byte type.
//       Converted '1' to 1.
//       Converted '08' to 8.
//       '0F' is not in the correct format for a base 10 conversion.
//       Converted '11' to 11.
//       Converted '12' to 12.
//       Converted '30' to 30.
//       Converted '101' to 101.
//       Converted '255' to 255.
//       'FF' is not in the correct format for a base 10 conversion.
//       '10000000' is outside the range of the Byte type.
//       Converted '80' to 80.
//    Base 16:
//       '-1' is invalid in base 16.
//       Converted '1' to 1.
//       Converted '08' to 8.
//       Converted '0F' to 15.
//       Converted '11' to 17.
//       Converted '12' to 18.
//       Converted '30' to 48.
//       '101' is outside the range of the Byte type.
//       '255' is outside the range of the Byte type.
//       Converted 'FF' to 255.
//       '10000000' is outside the range of the Byte type.
//       Converted '80' to 128.
Module Example
   Public Sub Main()
      Dim bases() As Integer = { 2, 8, 10, 16 }
      Dim values() As String = { "-1", "1", "08", "0F", "11" , "12", "30", _                
                                  "101", "255", "FF", "10000000", "80" }
      Dim number As Byte
      For Each base As Integer In bases
         Console.WriteLine("Base {0}:", base)
         For Each value As String In values
            Try
               number = Convert.ToByte(value, base)
               Console.WriteLine("   Converted '{0}' to {1}.", value, number)
            Catch e As FormatException
               Console.WriteLine("   '{0}' is not in the correct format for a base {1} conversion.", _
                                 value, base)
            Catch e As OverflowException
               Console.WriteLine("   '{0}' is outside the range of the Byte type.", value)
            Catch e As ArgumentException
               Console.WriteLine("   '{0}' is invalid in base {1}.", value, base)
            End Try   
         Next                                 
      Next 
   End Sub
End Module
' The example displays the following output:
'    Base 2:
'       '-1' is invalid in base 2.
'       Converted '1' to 1.
'       '08' is not in the correct format for a base 2 conversion.
'       '0F' is not in the correct format for a base 2 conversion.
'       Converted '11' to 3.
'       '12' is not in the correct format for a base 2 conversion.
'       '30' is not in the correct format for a base 2 conversion.
'       Converted '101' to 5.
'       '255' is not in the correct format for a base 2 conversion.
'       'FF' is not in the correct format for a base 2 conversion.
'       Converted '10000000' to 128.
'       '80' is not in the correct format for a base 2 conversion.
'    Base 8:
'       '-1' is invalid in base 8.
'       Converted '1' to 1.
'       '08' is not in the correct format for a base 8 conversion.
'       '0F' is not in the correct format for a base 8 conversion.
'       Converted '11' to 9.
'       Converted '12' to 10.
'       Converted '30' to 24.
'       Converted '101' to 65.
'       Converted '255' to 173.
'       'FF' is not in the correct format for a base 8 conversion.
'       '10000000' is outside the range of the Byte type.
'       '80' is not in the correct format for a base 8 conversion.
'    Base 10:
'       '-1' is outside the range of the Byte type.
'       Converted '1' to 1.
'       Converted '08' to 8.
'       '0F' is not in the correct format for a base 10 conversion.
'       Converted '11' to 11.
'       Converted '12' to 12.
'       Converted '30' to 30.
'       Converted '101' to 101.
'       Converted '255' to 255.
'       'FF' is not in the correct format for a base 10 conversion.
'       '10000000' is outside the range of the Byte type.
'       Converted '80' to 80.
'    Base 16:
'       '-1' is invalid in base 16.
'       Converted '1' to 1.
'       Converted '08' to 8.
'       Converted '0F' to 15.
'       Converted '11' to 17.
'       Converted '12' to 18.
'       Converted '30' to 48.
'       '101' is outside the range of the Byte type.
'       '255' is outside the range of the Byte type.
'       Converted 'FF' to 255.
'       '10000000' is outside the range of the Byte type.
'       Converted '80' to 128.

注釈

fromBase 16 の場合は、 valueパラメーターで指定された数値の先頭に "0x" または "0x" を付けることができます。If fromBase is 16, you can prefix the number specified by the value parameter with "0x" or "0X".

データ型Byteは符号なしの値のみをサポートToByte(String, Int32)するため、 valueメソッドは、が符号なしのバイナリ表現を使用して表現されることを前提としています。Because the Byte data type supports unsigned values only, the ToByte(String, Int32) method assumes that value is expressed using unsigned binary representation. つまり、8ビットはすべて数値を表すために使用され、符号ビットは存在しません。In other words, all eight bits are used to represent the numeric value, and a sign bit is absent. その結果、メソッドによって例外がスローされることなく、 Byteデータ型の範囲外にある符号付きバイト値がByte値に変換されるコードを記述することができます。As a result, it is possible to write code in which a signed byte value that is out of the range of the Byte data type is converted to a Byte value without the method throwing an exception. 次の例でMinValueは、を16進数の文字列形式に変換ToByte(String, Int32)してから、メソッドを呼び出します。The following example converts MinValue to its hexadecimal string representation, and then calls the ToByte(String, Int32) method. このメソッドは、例外をスローする代わりに、"0x80 を128に変換する" というメッセージを表示します。Instead of throwing an exception, the method displays the message, "0x80 converts to 128."

// Create a hexadecimal value out of range of the Byte type.
string value = SByte.MinValue.ToString("X");
// Convert it back to a number.
try
{
   byte number = Convert.ToByte(value, 16);
   Console.WriteLine("0x{0} converts to {1}.", value, number);
}   
catch (OverflowException)
{
   Console.WriteLine("Unable to convert '0x{0}' to a byte.", value);
}   
' Create a hexadecimal value out of range of the Byte type.
Dim value As String = SByte.MinValue.ToString("X")
' Convert it back to a number.
Try
   Dim number As Byte = Convert.ToByte(value, 16)
   Console.WriteLine("0x{0} converts to {1}.", value, number)
Catch e As OverflowException
   Console.WriteLine("Unable to convert '0x{0}' to a byte.", value)
End Try   

バイナリ演算または数値変換を実行する場合、メソッドまたは演算子が特定の値を解釈するために適切な数値表現を使用しているかどうかを確認するのは常に開発者の責任です。When performing binary operations or numeric conversions, it is always the responsibility of the developer to verify that a method or operator is using the appropriate numeric representation to interpret a particular value. 次の例は、16進数の文字列形式をByte値に変換するときに、メソッドが符号なしバイナリ表現を不適切に使用しないようにするための1つの方法を示しています。The following example illustrates one technique for ensuring that the method does not inappropriately use unsigned binary representation when it converts a hexadecimal string representation to a Byte value. この例では、値がその値を文字列形式に変換している間に、符号付き整数または符号なし整数を表すかどうかを判断します。The example determines whether a value represents a signed or an unsigned integer while it is converting that value to its string representation. この例で値をByte値に変換すると、元の値が符号付き整数であるかどうかがチェックされます。When the example converts the value back to a Byte value, it checks whether the original value was a signed integer. そのような場合に、上位ビットが設定されている (値が負であり、符号なしバイナリ表現ではなく2つの補数を使用している) 場合、メソッドは例外をスローします。If so, and if its high-order bit is set (which indicates that the value is negative and that it uses two's complement instead of unsigned binary representation), the method throws an exception.

// Create a negative hexadecimal value out of range of the Byte type.
sbyte sourceNumber = SByte.MinValue;
bool isSigned = Math.Sign((sbyte)sourceNumber.GetType().GetField("MinValue").GetValue(null)) == -1;
string value = sourceNumber.ToString("X");
byte targetNumber;
try
{
   targetNumber = Convert.ToByte(value, 16);
   if (isSigned && ((targetNumber & 0x80) != 0))
      throw new OverflowException();
   else 
      Console.WriteLine("0x{0} converts to {1}.", value, targetNumber);
}
catch (OverflowException)
{
   Console.WriteLine("Unable to convert '0x{0}' to an unsigned byte.", value);
} 
// Displays the following to the console:
//    Unable to convert '0x80' to an unsigned byte.     
' Create a negative hexadecimal value out of range of the Byte type.
Dim sourceNumber As SByte = SByte.MinValue
Dim isSigned As Boolean = Math.Sign(sourceNumber.MinValue) = -1
Dim value As String = sourceNumber.ToString("X")
Dim targetNumber As Byte
Try
   targetNumber = Convert.ToByte(value, 16)
   If isSigned And ((targetNumber And &H80) <> 0) Then
      Throw New OverflowException()
   Else 
      Console.WriteLine("0x{0} converts to {1}.", value, targetNumber)
   End If    
Catch e As OverflowException
   Console.WriteLine("Unable to convert '0x{0}' to an unsigned byte.", value)
End Try 
' Displays the following to the console:
'    Unable to convert '0x80' to an unsigned byte.     

ToByte(Object, IFormatProvider) ToByte(Object, IFormatProvider) ToByte(Object, IFormatProvider) ToByte(Object, IFormatProvider)

指定したカルチャに固有の書式情報を使用して、指定したオブジェクトの値を 8 ビット符号なし整数に変換します。Converts the value of the specified object to an 8-bit unsigned integer, using the specified culture-specific formatting information.

public:
 static System::Byte ToByte(System::Object ^ value, IFormatProvider ^ provider);
public static byte ToByte (object value, IFormatProvider provider);
static member ToByte : obj * IFormatProvider -> byte
Public Shared Function ToByte (value As Object, provider As IFormatProvider) As Byte

パラメーター

value
Object Object Object Object

IConvertible インターフェイスを実装するオブジェクト。An object that implements the IConvertible interface.

provider
IFormatProvider IFormatProvider IFormatProvider IFormatProvider

カルチャ固有の書式情報を提供するオブジェクト。An object that supplies culture-specific formatting information.

戻り値

value と等価の 8 ビット符号なし整数。valuenull の場合は 0。An 8-bit unsigned integer that is equivalent to value, or zero if value is null.

例外

valueByte 値のプロパティの形式ではありません。value is not in the property format for a Byte value.

valueIConvertible を実装していません。value does not implement IConvertible.

- または --or- value から Byte 型への変換はサポートされていません。Conversion from value to the Byte type is not supported.

valueMinValue 未満の数値か、MaxValue より大きい数値を表します。value represents a number that is less than MinValue or greater than MaxValue.

次の例では、 ByteString インターフェイスを実装する IConvertible クラスを定義しています。The following example defines a ByteString class that implements the IConvertible interface. クラスは、バイト値の文字列形式と符号フィールドを格納して、符号付きと符号なしの両方のバイト値を表すことができるようにします。The class stores the string representation of a byte value along with a sign field, so that it is able to represent both signed and unsigned byte values.

using System;
using System.Globalization;

public enum SignBit { Negative=-1, Zero=0, Positive=1 };

public struct ByteString : IConvertible
{
   private SignBit signBit;
   private string byteString;
   
   public SignBit Sign
   { 
      set { signBit = value; }
      get { return signBit; }
   }

   public string Value
   { 
      set {
         if (value.Trim().Length > 2)
            throw new ArgumentException("The string representation of a byte cannot have more than two characters.");
         else
            byteString = value;
      }
      get { return byteString; }
   }
   
   // IConvertible implementations.
   public TypeCode GetTypeCode() {
      return TypeCode.Object;
   }
   
   public bool ToBoolean(IFormatProvider provider)
   {
      if (signBit == SignBit.Zero)
         return false;
      else
         return true;
   } 
   
   public byte ToByte(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         throw new OverflowException(String.Format("{0} is out of range of the Byte type.", Convert.ToSByte(byteString, 16)));
      else
         return Byte.Parse(byteString, NumberStyles.HexNumber);
   }
   
   public char ToChar(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative) { 
         throw new OverflowException(String.Format("{0} is out of range of the Char type.", Convert.ToSByte(byteString, 16)));
      }
      else {
         byte byteValue = Byte.Parse(this.byteString, NumberStyles.HexNumber);
         return Convert.ToChar(byteValue);
      }                
   } 
   
   public DateTime ToDateTime(IFormatProvider provider)
   {
      throw new InvalidCastException("ByteString to DateTime conversion is not supported.");
   }
   
   public decimal ToDecimal(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative) 
      {
         sbyte byteValue = SByte.Parse(byteString, NumberStyles.HexNumber);
         return Convert.ToDecimal(byteValue);
      }
      else 
      {
         byte byteValue = Byte.Parse(byteString, NumberStyles.HexNumber);
         return Convert.ToDecimal(byteValue);
      }
   }
   
   public double ToDouble(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         return Convert.ToDouble(SByte.Parse(byteString, NumberStyles.HexNumber));
      else
         return Convert.ToDouble(Byte.Parse(byteString, NumberStyles.HexNumber));
   }   
   
   public short ToInt16(IFormatProvider provider) 
   {
      if (signBit == SignBit.Negative)
         return Convert.ToInt16(SByte.Parse(byteString, NumberStyles.HexNumber));
      else
         return Convert.ToInt16(Byte.Parse(byteString, NumberStyles.HexNumber));
   }
   
   public int ToInt32(IFormatProvider provider) 
   {
      if (signBit == SignBit.Negative)
         return Convert.ToInt32(SByte.Parse(byteString, NumberStyles.HexNumber));
      else
         return Convert.ToInt32(Byte.Parse(byteString, NumberStyles.HexNumber));
   }
   
   public long ToInt64(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         return Convert.ToInt64(SByte.Parse(byteString, NumberStyles.HexNumber));
      else
         return Convert.ToInt64(Byte.Parse(byteString, NumberStyles.HexNumber));
   }
   
   public sbyte ToSByte(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         try {
            return Convert.ToSByte(Byte.Parse(byteString, NumberStyles.HexNumber));
         }
         catch (OverflowException e) {
            throw new OverflowException(String.Format("{0} is outside the range of the SByte type.", 
                                                   Byte.Parse(byteString, NumberStyles.HexNumber)), e);
         }
      else   
         return SByte.Parse(byteString, NumberStyles.HexNumber);
   }

   public float ToSingle(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         return Convert.ToSingle(SByte.Parse(byteString, NumberStyles.HexNumber));
      else
         return Convert.ToSingle(Byte.Parse(byteString, NumberStyles.HexNumber));
   }

   public string ToString(IFormatProvider provider)
   {
      return "0x" + this.byteString;
   }
   
   public object ToType(Type conversionType, IFormatProvider provider)
   {
      switch (Type.GetTypeCode(conversionType))
      {
         case TypeCode.Boolean: 
            return this.ToBoolean(null);
         case TypeCode.Byte:
            return this.ToByte(null);
         case TypeCode.Char:
            return this.ToChar(null);
         case TypeCode.DateTime:
            return this.ToDateTime(null);
         case TypeCode.Decimal:
            return this.ToDecimal(null);
         case TypeCode.Double:
            return this.ToDouble(null);
         case TypeCode.Int16:
            return this.ToInt16(null);
         case TypeCode.Int32:
            return this.ToInt32(null);
         case TypeCode.Int64:
            return this.ToInt64(null);
         case TypeCode.Object:
            if (typeof(ByteString).Equals(conversionType))
               return this;
            else
               throw new InvalidCastException(String.Format("Conversion to a {0} is not supported.", conversionType.Name));
         case TypeCode.SByte:
            return this.ToSByte(null);
         case TypeCode.Single:
            return this.ToSingle(null);
         case TypeCode.String:
            return this.ToString(null);
         case TypeCode.UInt16:
            return this.ToUInt16(null);
         case TypeCode.UInt32:
            return this.ToUInt32(null);
         case TypeCode.UInt64:
            return this.ToUInt64(null);   
         default:
            throw new InvalidCastException(String.Format("Conversion to {0} is not supported.", conversionType.Name));   
      }
   }
   
   public UInt16 ToUInt16(IFormatProvider provider) 
   {
      if (signBit == SignBit.Negative)
         throw new OverflowException(String.Format("{0} is outside the range of the UInt16 type.", 
                                                   SByte.Parse(byteString, NumberStyles.HexNumber)));
      else
         return Convert.ToUInt16(Byte.Parse(byteString, NumberStyles.HexNumber));
   }

   public UInt32 ToUInt32(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         throw new OverflowException(String.Format("{0} is outside the range of the UInt32 type.", 
                                                   SByte.Parse(byteString, NumberStyles.HexNumber)));
      else
         return Convert.ToUInt32(Byte.Parse(byteString, NumberStyles.HexNumber));
   }
   
   public UInt64 ToUInt64(IFormatProvider provider) 
   {
      if (signBit == SignBit.Negative)
         throw new OverflowException(String.Format("{0} is outside the range of the UInt64 type.", 
                                                   SByte.Parse(byteString, NumberStyles.HexNumber)));
      else
         return Convert.ToUInt64(Byte.Parse(byteString, NumberStyles.HexNumber));
   }
}
Imports System.Globalization

Public Enum SignBit As Integer
   Positive = 1
   Zero = 0
   Negative = -1
End Enum

Public Structure ByteString : Implements IConvertible
   Private signBit As SignBit
   Private byteString As String
   
   Public Property Sign As SignBit
      Set
         signBit = value
      End Set
      Get
         Return signBit
      End Get
   End Property
   
   Public Property Value As String
      Set
         If value.Trim().Length > 2 Then
            Throw New ArgumentException("The string representation of a byte cannot have more than two characters.")
         Else
            byteString = value
         End If   
      End Set
      Get
         Return byteString
      End Get
   End Property
   
   ' IConvertible implementations.
   Public Function GetTypeCode() As TypeCode _
                   Implements IConvertible.GetTypeCode
      Return TypeCode.Object
   End Function
   
   Public Function ToBoolean(provider As IFormatProvider) As Boolean _
                   Implements IConvertible.ToBoolean
      If signBit = SignBit.Zero Then
         Return False
      Else
         Return True
      End If
   End Function 
   
   Public Function ToByte(provider As IFormatProvider) As Byte _
                   Implements IConvertible.ToByte
      If signBit = signBit.Negative Then
         Throw New OverflowException(String.Format("{0} is out of range of the Byte type.", Convert.ToSByte(byteString, 16))) 
      Else
         Return Byte.Parse(byteString, NumberStyles.HexNumber)
      End If       
   End Function
   
   Public Function ToChar(provider As IFormatProvider) As Char _
                   Implements IConvertible.ToChar
      If signBit = signBit.Negative Then 
         Throw New OverflowException(String.Format("{0} is out of range of the Char type.", Convert.ToSByte(byteString, 16)))
      Else
         Dim byteValue As Byte = Byte.Parse(Me.byteString, NumberStyles.HexNumber)
         Return Convert.ToChar(byteValue)
      End If                
   End Function 
   
   Public Function ToDateTime(provider As IFormatProvider) As Date _
                   Implements IConvertible.ToDateTime
      Throw New InvalidCastException("ByteString to DateTime conversion is not supported.")
   End Function
   
   Public Function ToDecimal(provider As IFormatProvider) As Decimal _
                   Implements IConvertible.ToDecimal
      If signBit = signBit.Negative Then
         Dim byteValue As SByte = SByte.Parse(byteString, NumberStyles.HexNumber)
         Return Convert.ToDecimal(byteValue)
      Else
         Dim byteValue As Byte = Byte.Parse(byteString, NumberStyles.HexNumber)
         Return Convert.ToDecimal(byteValue)
      End If
   End Function
   
   Public Function ToDouble(provider As IFormatProvider) As Double _
                   Implements IConvertible.ToDouble
      If signBit = signBit.Negative Then
         Return Convert.ToDouble(SByte.Parse(byteString, NumberStyles.HexNumber))
      Else
         Return Convert.ToDouble(Byte.Parse(byteString, NumberStyles.HexNumber))
      End If   
   End Function   
   
   Public Function ToInt16(provider As IFormatProvider) As Int16 _
                   Implements IConvertible.ToInt16
      If signBit = signBit.Negative Then
         Return Convert.ToInt16(SByte.Parse(byteString, NumberStyles.HexNumber))
      Else
         Return Convert.ToInt16(Byte.Parse(byteString, NumberStyles.HexNumber))
      End If   
   End Function
   
   Public Function ToInt32(provider As IFormatProvider) As Int32 _
                   Implements IConvertible.ToInt32
      If signBit = signBit.Negative Then
         Return Convert.ToInt32(SByte.Parse(byteString, NumberStyles.HexNumber))
      Else
         Return Convert.ToInt32(Byte.Parse(byteString, NumberStyles.HexNumber))
      End If   
   End Function
   
   Public Function ToInt64(provider As IFormatProvider) As Int64 _
                   Implements IConvertible.ToInt64
      If signBit = signBit.Negative Then
         Return Convert.ToInt64(SByte.Parse(byteString, NumberStyles.HexNumber))
      Else
         Return Convert.ToInt64(Byte.Parse(byteString, NumberStyles.HexNumber))
      End If   
   End Function
   
   Public Function ToSByte(provider As IFormatProvider) As SByte _
                   Implements IConvertible.ToSByte
      If signBit = SignBit.Positive Then
         Try
            Return Convert.ToSByte(Byte.Parse(byteString, NumberStyles.HexNumber))
         Catch e As OverflowException
            Throw New OverflowException(String.Format("{0} is outside the range of the SByte type.", _
                                                   Byte.Parse(byteString, NumberStyles.HexNumber)), e)   
         End Try
      Else
         Return SByte.Parse(byteString, NumberStyles.HexNumber)
      End If
   End Function

   Public Function ToSingle(provider As IFormatProvider) As Single _
                   Implements IConvertible.ToSingle
      If signBit = signBit.Negative Then
         Return Convert.ToSingle(SByte.Parse(byteString, NumberStyles.HexNumber))
      Else
         Return Convert.ToSingle(Byte.Parse(byteString, NumberStyles.HexNumber))
      End If   
   End Function

   Public Overloads Function ToString(provider As IFormatProvider) As String _
                   Implements IConvertible.ToString
      Return Me.byteString
   End Function
   
   Public Function ToType(conversionType As Type, provider As IFormatProvider) As Object _
                   Implements IConvertible.ToType
      Select Case Type.GetTypeCode(conversionType)
         Case TypeCode.Boolean 
            Return Me.ToBoolean(Nothing)
         Case TypeCode.Byte
            Return Me.ToByte(Nothing)
         Case TypeCode.Char
            Return Me.ToChar(Nothing)
         Case TypeCode.DateTime
            Return Me.ToDateTime(Nothing)
         Case TypeCode.Decimal
            Return Me.ToDecimal(Nothing)
         Case TypeCode.Double
            Return Me.ToDouble(Nothing)
         Case TypeCode.Int16
            Return Me.ToInt16(Nothing)
         Case TypeCode.Int32
            Return Me.ToInt32(Nothing)
         Case TypeCode.Int64
            Return Me.ToInt64(Nothing)
         Case TypeCode.Object
            If GetType(ByteString).Equals(conversionType) Then
               Return Me
            Else
               Throw New InvalidCastException(String.Format("Conversion to a {0} is not supported.", conversionType.Name))
            End If 
         Case TypeCode.SByte
            Return Me.ToSByte(Nothing)
         Case TypeCode.Single
            Return Me.ToSingle(Nothing)
         Case TypeCode.String
            Return Me.ToString(Nothing)
         Case TypeCode.UInt16
            Return Me.ToUInt16(Nothing)
         Case TypeCode.UInt32
            Return Me.ToUInt32(Nothing)
         Case TypeCode.UInt64
            Return Me.ToUInt64(Nothing)   
         Case Else
            Throw New InvalidCastException(String.Format("Conversion to {0} is not supported.", conversionType.Name))   
            
      End Select
   End Function
   
   Public Function ToUInt16(provider As IFormatProvider) As UInt16 _
                   Implements IConvertible.ToUInt16
      If signBit = signBit.Negative Then
         Throw New OverflowException(String.Format("{0} is outside the range of the UInt16 type.", _
                                                   SByte.Parse(byteString, NumberStyles.HexNumber)))
      Else
         Return Convert.ToUInt16(Byte.Parse(byteString, NumberStyles.HexNumber))
      End If   
   End Function

   Public Function ToUInt32(provider As IFormatProvider) As UInt32 _
                   Implements IConvertible.ToUInt32
      If signBit = signBit.Negative Then
         Throw New OverflowException(String.Format("{0} is outside the range of the UInt32 type.", _
                                                   SByte.Parse(byteString, NumberStyles.HexNumber)))
      Else
         Return Convert.ToUInt32(Byte.Parse(byteString, NumberStyles.HexNumber))
      End If   
   End Function
   
   Public Function ToUInt64(provider As IFormatProvider) As UInt64 _
                   Implements IConvertible.ToUInt64
      If signBit = signBit.Negative Then
         Throw New OverflowException(String.Format("{0} is outside the range of the UInt64 type.", _
                                                   SByte.Parse(byteString, NumberStyles.HexNumber)))
      Else
         Return Convert.ToUInt64(Byte.Parse(byteString, NumberStyles.HexNumber))
      End If   
   End Function
   
End Structure

次の例ではByteString 、複数のオブジェクトToByte(Object, IFormatProvider)をインスタンス化し、メソッドを呼び出してそれらをバイト値に変換します。The following example instantiates several ByteString objects and calls the ToByte(Object, IFormatProvider) method to convert them to byte values. これは、メソッドToByte(Object, IFormatProvider)が、変換対象のオブジェクトIConvertible.ToByteのメソッドの呼び出しをラップすることを示しています。It illustrates that the ToByte(Object, IFormatProvider) method wraps a call to the IConvertible.ToByte method of the object to be converted.

public class Class1
{
   public static void Main()
   {
      byte positiveByte = 216;
      sbyte negativeByte = -101;
      
      
      ByteString positiveString = new ByteString();
      positiveString.Sign = (SignBit) Math.Sign(positiveByte);
      positiveString.Value = positiveByte.ToString("X2");
      
      ByteString negativeString = new ByteString();
      negativeString.Sign = (SignBit) Math.Sign(negativeByte);
      negativeString.Value = negativeByte.ToString("X2");
      
      try {
         Console.WriteLine("'{0}' converts to {1}.", positiveString.Value, Convert.ToByte(positiveString));
      }
      catch (OverflowException) {
         Console.WriteLine("0x{0} is outside the range of the Byte type.", positiveString.Value);
      }

      try {
         Console.WriteLine("'{0}' converts to {1}.", negativeString.Value, Convert.ToByte(negativeString));
      }
      catch (OverflowException) {
         Console.WriteLine("0x{0} is outside the range of the Byte type.", negativeString.Value);
      }   
   }
}
// The example displays the following output:
//       'D8' converts to 216.
//       0x9B is outside the range of the Byte type.
Module modMain
   Public Sub Main()
      Dim positiveByte As Byte = 216
      Dim negativeByte As SByte = -101
      
      
      Dim positiveString As New ByteString()
      positiveString.Sign = CType(Math.Sign(positiveByte), SignBit)
      positiveString.Value = positiveByte.ToString("X2")
      
      Dim negativeString As New ByteString()
      negativeString.Sign = CType(Math.Sign(negativeByte), SignBit)
      negativeString.Value = negativeByte.ToString("X2")
      
      Try
         Console.WriteLine("'{0}' converts to {1}.", positiveString.Value, Convert.ToByte(positiveString))
      Catch e As OverflowException
         Console.WriteLine("0x{0} is outside the range of the Byte type.", positiveString.Value)
      End Try

      Try
         Console.WriteLine("'{0}' converts to {1}.", negativeString.Value, Convert.ToByte(negativeString))
      Catch e As OverflowException
         Console.WriteLine("0x{0} is outside the range of the Byte type.", negativeString.Value)
      End Try   
   End Sub
End Module
' The example dosplays the following output:
'       'D8' converts to 216.
'       0x9B is outside the range of the Byte type.

注釈

providerユーザーがのvalueコンテンツに関するカルチャ固有の変換情報を指定できるようにします。provider enables the user to specify culture-specific conversion information about the contents of value. 基本型ではprovider無視されます。ただし、がIConvertibleインターフェイスvalueを実装するユーザー定義型である場合は、パラメーターを使用できます。The base types ignore provider; however, the parameter may be used if value is a user-defined type that implements the IConvertible interface.

ToByte(String, IFormatProvider) ToByte(String, IFormatProvider) ToByte(String, IFormatProvider) ToByte(String, IFormatProvider)

指定したカルチャに固有の書式情報を使用して、指定した数値の文字列形式を等価の 8 ビット符号なし整数に変換します。Converts the specified string representation of a number to an equivalent 8-bit unsigned integer, using specified culture-specific formatting information.

public:
 static System::Byte ToByte(System::String ^ value, IFormatProvider ^ provider);
public static byte ToByte (string value, IFormatProvider provider);
static member ToByte : string * IFormatProvider -> byte
Public Shared Function ToByte (value As String, provider As IFormatProvider) As Byte

パラメーター

value
String String String String

変換する数値を含んだ文字列。A string that contains the number to convert.

provider
IFormatProvider IFormatProvider IFormatProvider IFormatProvider

カルチャ固有の書式情報を提供するオブジェクト。An object that supplies culture-specific formatting information.

戻り値

value と等価の 8 ビット符号なし整数。valuenull の場合は 0。An 8-bit unsigned integer that is equivalent to value, or zero if value is null.

例外

value は、オプションの符号とそれに続く数字 (0 ~ 9) のシーケンスで構成されていません。value does not consist of an optional sign followed by a sequence of digits (0 through 9).

valueMinValue 未満の数値か、MaxValue より大きい数値を表します。value represents a number that is less than MinValue or greater than MaxValue.

次の例では、 NumberFormatInfo正符号を "pos" として定義し、負の符号を "neg" として定義するカスタムオブジェクトToByte(String, IFormatProvider)を作成します。これは、メソッドの呼び出しで使用されます。The following example creates a custom NumberFormatInfo object that defines the positive sign as "pos" and the negative sign as "neg", which it uses in calls to the ToByte(String, IFormatProvider) method. 次に、 ToByte(String, IFormatProvider)メソッドを繰り返し呼び出して、文字列配列の各要素をByte値に変換します。It then calls the ToByte(String, IFormatProvider) method repeatedly to convert each element in a string array to a Byte value.

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      // Create a NumberFormatInfo object and set several of its
      // properties that apply to unsigned bytes.
      NumberFormatInfo provider = new NumberFormatInfo();

      // These properties affect the conversion.
      provider.PositiveSign = "pos ";
      provider.NegativeSign = "neg ";

      // This property does not affect the conversion.
      // The input string cannot have a decimal separator.
      provider.NumberDecimalSeparator = ".";
      
      // Define an array of numeric strings.
      string[] numericStrings = { "234", "+234", "pos 234", "234.", "255", 
                                  "256", "-1" };

      foreach (string numericString in numericStrings)
      {
         Console.Write("'{0,-8}' ->   ", numericString);
         try {
            byte number = Convert.ToByte(numericString, provider);
            Console.WriteLine(number);
         }   
         catch (FormatException) {
            Console.WriteLine("Incorrect Format");
         }                             
         catch (OverflowException) {
            Console.WriteLine("Overflows a Byte");
         }   
      }
   }
}
// The example displays the following output:
//       '234     ' ->   234
//       '+234    ' ->   Incorrect Format
//       'pos 234 ' ->   234
//       '234.    ' ->   Incorrect Format
//       '255     ' ->   255
//       '256     ' ->   Overflows a Byte
//       '-1      ' ->   Incorrect Format
Imports System.Globalization

Module Example
   Public Sub Main()
      ' Create a NumberFormatInfo object and set several of its
      ' properties that apply to unsigned bytes.
      Dim provider As New NumberFormatInfo()
      With provider 
         ' These properties affect the conversion.
         .PositiveSign = "pos "
         .NegativeSign = "neg "

         ' This property does not affect the conversion.
         ' The input string cannot have a decimal separator.
         .NumberDecimalSeparator = "."
      End With
      
      ' Define an array of numeric strings.
      Dim numericStrings() As String = { "234", "+234", "pos 234", "234.", _
                                         "255", "256", "-1" }

      For Each numericString As String In numericStrings
         Console.Write("'{0,-8}' ->   ", numericString)
         Try
            Dim number As Byte = Convert.ToByte(numericString, provider)
            Console.WriteLine(number)
         Catch ex As FormatException
            Console.WriteLine("Incorrect Format")                          
         Catch ex As OverflowException
            Console.WriteLine("Overflows a Byte")
         End Try   
      Next
   End Sub   
End Module 
' The example displays the following output:
'       '234     ' ->   234
'       '+234    ' ->   Incorrect Format
'       'pos 234 ' ->   234
'       '234.    ' ->   Incorrect Format
'       '255     ' ->   255
'       '256     ' ->   Overflows a Byte
'       '-1      ' ->   Incorrect Format

注釈

providerは、オブジェクトをNumberFormatInfo取得するインスタンスです。IFormatProviderprovider is an IFormatProvider instance that obtains a NumberFormatInfo object. オブジェクトNumberFormatInfoは、の書式に関するカルチャ固有のvalue情報を提供します。The NumberFormatInfo object provides culture-specific information about the format of value. NumberFormatInfoprovider の場合は、現在のカルチャのオブジェクトが使用されます。nullIf provider is null, the NumberFormatInfo object for the current culture is used.

変換に失敗した場合に例外を処理したくない場合は、代わりにByte.TryParseメソッドを呼び出すことができます。If you prefer not to handle an exception if the conversion fails, you can call the Byte.TryParse method instead. 変換が成功Booleanしたか失敗したかを示す値を返します。It returns a Boolean value that indicates whether the conversion succeeded or failed.

こちらもご覧ください

ToByte(Single) ToByte(Single) ToByte(Single) ToByte(Single)

指定した単精度浮動小数点数値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified single-precision floating-point number to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(float value);
public static byte ToByte (float value);
static member ToByte : single -> byte
Public Shared Function ToByte (value As Single) As Byte

パラメーター

value
Single Single Single Single

単精度浮動小数点数。A single-precision floating-point number.

戻り値

近似値の 8 ビット符号なし整数に丸められた valuevalue, rounded to the nearest 8-bit unsigned integer. value が 2 つの整数のちょうど中間にある場合は、偶数が返されます。つまり、4.5 は 4 に変換され、5.5 は 6 に変換されます。If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

例外

valueMaxValue を超えているか、または MinValue 未満です。value is greater than MaxValue or less than MinValue.

次の例ではSingle 、値をByteに変換します。The following example converts a Single value to a Byte.

public:
   void ConvertByteSingle( Byte byteVal )
   {
      float floatVal;
      
      // Byte to float conversion will not overflow.
      floatVal = System::Convert::ToSingle( byteVal );
      System::Console::WriteLine( "The Byte as a float is {0}.",
         floatVal );
      
      // Float to Byte conversion can overflow.
      try
      {
         byteVal = System::Convert::ToByte( floatVal );
         System::Console::WriteLine( "The float as a Byte is {0}.",
         byteVal );
      }
      catch ( System::OverflowException^ ) 
      {
         System::Console::WriteLine(
            "The float value is too large for a Byte." );
      }
   }
public void ConvertByteSingle(byte byteVal) {
	float floatVal;

	// Byte to float conversion will not overflow.
	floatVal = System.Convert.ToSingle(byteVal);
	System.Console.WriteLine("The byte as a float is {0}.",
		floatVal);

	// Float to byte conversion can overflow.
	try {
		byteVal = System.Convert.ToByte(floatVal);
		System.Console.WriteLine("The float as a byte is {0}.",
			byteVal);
	}
	catch (System.OverflowException) {
		System.Console.WriteLine(
			"The float value is too large for a byte.");
	}
}
Public Sub ConvertByteSingle(ByVal byteVal As Byte)
    Dim singleVal As Single

    ' Byte to float conversion will not overflow.
    singleVal = System.Convert.ToSingle(byteVal)
    System.Console.WriteLine("The byte as a single is {0}.", _
                              singleVal)

    ' Single to byte conversion can overflow.
    Try
        byteVal = System.Convert.ToByte(singleVal)
        System.Console.WriteLine("The single as a byte is {0}.", _
                                  byteVal)
    Catch exception As System.OverflowException
        System.Console.WriteLine( _
            "Overflow in single-to-byte conversion.")
    End Try
End Sub
こちらもご覧ください

ToByte(UInt64) ToByte(UInt64) ToByte(UInt64) ToByte(UInt64)

重要

この API は CLS 準拠ではありません。

指定した 64 ビット符号なし整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 64-bit unsigned integer to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(System::UInt64 value);
[System.CLSCompliant(false)]
public static byte ToByte (ulong value);
static member ToByte : uint64 -> byte
Public Shared Function ToByte (value As ULong) As Byte

パラメーター

value
UInt64 UInt64 UInt64 UInt64

変換する 64 ビット符号なし整数。The 64-bit unsigned integer to convert.

戻り値

value と等価の 8 ビット符号なし整数。An 8-bit unsigned integer that is equivalent to value.

例外

valueMaxValue より大きくなっています。value is greater than MaxValue.

次の例では、符号なし長整数のByte配列を値に変換します。The following example converts an array of unsigned long integers to Byte values.

ulong[] numbers= { UInt64.MinValue, 121, 340, UInt64.MaxValue };
byte result;
foreach (ulong number in numbers)
{
   try {
      result = Convert.ToByte(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", 
                        number.GetType().Name, number, 
                        result.GetType().Name, result);
   }                     
   catch (OverflowException)
   {
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", 
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//       Converted the UInt64 value 0 to the Byte value 0.
//       Converted the UInt64 value 121 to the Byte value 121.
//       The UInt64 value 340 is outside the range of the Byte type.
//       The UInt64 value 18446744073709551615 is outside the range of the Byte type.
Dim numbers() As ULong = { UInt64.MinValue, 121, 340, UInt64.MaxValue }
Dim result As Byte
For Each number As ULong In numbers
   Try
      result = Convert.ToByte(number)
      Console.WriteLIne("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'       Converted the UInt64 value 0 to the Byte value 0.
'       Converted the UInt64 value 121 to the Byte value 121.
'       The UInt64 value 340 is outside the range of the Byte type.
'       The UInt64 value 18446744073709551615 is outside the range of the Byte type.

ToByte(SByte) ToByte(SByte) ToByte(SByte) ToByte(SByte)

重要

この API は CLS 準拠ではありません。

指定した 8 ビット符号付き整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 8-bit signed integer to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(System::SByte value);
[System.CLSCompliant(false)]
public static byte ToByte (sbyte value);
static member ToByte : sbyte -> byte
Public Shared Function ToByte (value As SByte) As Byte

パラメーター

value
SByte SByte SByte SByte

変換する 8 ビット符号付き整数。The 8-bit signed integer to be converted.

戻り値

value と等価の 8 ビット符号なし整数。An 8-bit unsigned integer that is equivalent to value.

例外

valueMinValue より小さい値です。value is less than MinValue.

次の例では、値SByteの配列Byteを値に変換します。The following example converts an array of SByte values to Byte values.

sbyte[] numbers = { SByte.MinValue, -1, 0, 10, SByte.MaxValue };
byte result;
foreach (sbyte number in numbers)
{
   try {
      result = Convert.ToByte(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", 
                        number.GetType().Name, number, 
                        result.GetType().Name, result);
   }                     
   catch (OverflowException)
   {
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", 
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//       The SByte value -128 is outside the range of the Byte type.
//       The SByte value -1 is outside the range of the Byte type.
//       Converted the SByte value 0 to the Byte value 0.
//       Converted the SByte value 10 to the Byte value 10.
//       Converted the SByte value 127 to the Byte value 127.
Dim numbers() As SByte = { SByte.MinValue, -1, 0, 10, SByte.MaxValue }
Dim result As Byte
For Each number As SByte In numbers
   Try
      result = Convert.ToByte(number)
      Console.WriteLIne("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'       The SByte value -128 is outside the range of the Byte type.
'       The SByte value -1 is outside the range of the Byte type.
'       Converted the SByte value 0 to the Byte value 0.
'       Converted the SByte value 10 to the Byte value 10.
'       Converted the SByte value 127 to the Byte value 127.

ToByte(Double) ToByte(Double) ToByte(Double) ToByte(Double)

指定した倍精度浮動小数点数値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified double-precision floating-point number to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(double value);
public static byte ToByte (double value);
static member ToByte : double -> byte
Public Shared Function ToByte (value As Double) As Byte

パラメーター

value
Double Double Double Double

変換する倍精度浮動小数点数。The double-precision floating-point number to convert.

戻り値

近似値の 8 ビット符号なし整数に丸められた valuevalue, rounded to the nearest 8-bit unsigned integer. value が 2 つの整数のちょうど中間にある場合は、偶数が返されます。つまり、4.5 は 4 に変換され、5.5 は 6 に変換されます。If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

例外

valueMaxValue を超えているか、または MinValue 未満です。value is greater than MaxValue or less than MinValue.

次の例ではByte 、値Double Doubleをに変換し、値Byteをに変換します。The following example converts a Byte value to a Double and a Double value to a Byte.

public:
   void ConvertDoubleByte( double doubleVal )
   {
      Byte byteVal = 0;
      
      // Double to Byte conversion can overflow.
      try
      {
         byteVal = System::Convert::ToByte( doubleVal );
         System::Console::WriteLine( " {0} as a Byte is: {1}.",
         doubleVal, byteVal );
      }
      catch ( System::OverflowException^ ) 
      {
         System::Console::WriteLine( "Overflow in double-to-Byte conversion." );
      }
      
      // Byte to double conversion cannot overflow.
      doubleVal = System::Convert::ToDouble( byteVal );
      System::Console::WriteLine( " {0} as a double is: {1}.",
         byteVal, doubleVal );
   }
public void ConvertDoubleByte(double doubleVal) {
	byte	byteVal = 0;

	// Double to byte conversion can overflow.
	try {
		byteVal = System.Convert.ToByte(doubleVal);
		System.Console.WriteLine("{0} as a byte is: {1}.",
			doubleVal, byteVal);
	} 
	catch (System.OverflowException) {
		System.Console.WriteLine(
			"Overflow in double-to-byte conversion.");
	}

	// Byte to double conversion cannot overflow.
	doubleVal = System.Convert.ToDouble(byteVal);
	System.Console.WriteLine("{0} as a double is: {1}.",
		byteVal, doubleVal);
}
Public Sub ConvertDoubleByte(ByVal doubleVal As Double)
    Dim byteVal As Byte = 0

    ' Double to Byte conversion can overflow.
    Try
        byteVal = System.Convert.ToByte(doubleVal)
        System.Console.WriteLine("{0} as a Byte is: {1}.", _
            doubleVal, byteVal)
    Catch exception As System.OverflowException
        System.Console.WriteLine( _
            "Overflow in Double-to-Byte conversion.")
    End Try

    ' Byte to Double conversion cannot overflow.
    doubleVal = System.Convert.ToDouble(byteVal)
    System.Console.WriteLine("{0} as a Double is: {1}.", _
                              byteVal, doubleVal)
End Sub

ToByte(Int64) ToByte(Int64) ToByte(Int64) ToByte(Int64)

指定した 64 ビット符号付き整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 64-bit signed integer to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(long value);
public static byte ToByte (long value);
static member ToByte : int64 -> byte
Public Shared Function ToByte (value As Long) As Byte

パラメーター

value
Int64 Int64 Int64 Int64

変換する 64 ビット符号付き整数。The 64-bit signed integer to convert.

戻り値

value と等価の 8 ビット符号なし整数。An 8-bit unsigned integer that is equivalent to value.

例外

valueMinValue より小さいか MaxValue より大きいです。value is less than MinValue or greater than MaxValue.

次の例では、値Int64の配列Byteを値に変換します。The following example converts an array of Int64 values to Byte values.

long[] numbers = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue };
byte result;
foreach (long number in numbers)
{
   try {
      result = Convert.ToByte(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", 
                        number.GetType().Name, number, 
                        result.GetType().Name, result);
   }                     
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", 
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//       The Int64 value -9223372036854775808 is outside the range of the Byte type.
//       The Int64 value -1 is outside the range of the Byte type.
//       Converted the Int64 value 0 to the Byte value 0.
//       Converted the Int64 value 121 to the Byte value 121.
//       The Int64 value 340 is outside the range of the Byte type.
//       The Int64 value 9223372036854775807 is outside the range of the Byte type.      
Dim numbers() As Long = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue }
Dim result As Byte
For Each number As Long In numbers
   Try
      result = Convert.ToByte(number)
      Console.WriteLIne("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'       The Int64 value -9223372036854775808 is outside the range of the Byte type.
'       The Int64 value -1 is outside the range of the Byte type.
'       Converted the Int64 value 0 to the Byte value 0.
'       Converted the Int64 value 121 to the Byte value 121.
'       The Int64 value 340 is outside the range of the Byte type.
'       The Int64 value 9223372036854775807 is outside the range of the Byte type.      

ToByte(Byte) ToByte(Byte) ToByte(Byte) ToByte(Byte)

指定した 8 ビット符号なし整数が返されます。実際の変換は行われません。Returns the specified 8-bit unsigned integer; no actual conversion is performed.

public:
 static System::Byte ToByte(System::Byte value);
public static byte ToByte (byte value);
static member ToByte : byte -> byte
Public Shared Function ToByte (value As Byte) As Byte

パラメーター

value
Byte Byte Byte Byte

返される 8 ビット符号なし整数。The 8-bit unsigned integer to return.

戻り値

value は変更されずに返されます。value is returned unchanged.

ToByte(Char) ToByte(Char) ToByte(Char) ToByte(Char)

指定した Unicode 文字の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified Unicode character to the equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(char value);
public static byte ToByte (char value);
static member ToByte : char -> byte
Public Shared Function ToByte (value As Char) As Byte

パラメーター

value
Char Char Char Char

変換する Unicode 文字。The Unicode character to convert.

戻り値

value と等価の 8 ビット符号なし整数。An 8-bit unsigned integer that is equivalent to value.

例外

valueMaxValue より大きい数値を表します。value represents a number that is greater than MaxValue.

次の例では、値Charの配列Byteを値に変換します。The following example converts an array of Char values to Byte values.

char[] chars = { 'a', 'z', '\x0007', '\x03FF' };
foreach (char ch in chars)
{
   try {
      byte result = Convert.ToByte(ch);
      Console.WriteLine("{0} is converted to {1}.", ch, result);
   }   
   catch (OverflowException) {
      Console.WriteLine("Unable to convert u+{0} to a byte.", 
                        Convert.ToInt16(ch).ToString("X4"));
   }
}   
// The example displays the following output:
//       a is converted to 97.
//       z is converted to 122.
//        is converted to 7.
//       Unable to convert u+03FF to a byte.      
Dim chars() As Char = { "a"c, "z"c, ChrW(7), ChrW(1023) }
For Each ch As Char in chars
   Try
      Dim result As Byte = Convert.ToByte(ch)
      Console.WriteLine("{0} is converted to {1}.", ch, result)
   Catch e As OverflowException
      Console.WriteLIne("Unable to convert u+{0} to a byte.", _
                        AscW(ch).ToString("X4"))
   End Try
Next   
' The example displays the following output:
'       a is converted to 97.
'       z is converted to 122.
'        is converted to 7.
'       Unable to convert u+03FF to a byte.      

注釈

このメソッドは、渡されたCharオブジェクトの数値コードを表す符号なしバイト値を返します。This method returns an unsigned byte value that represents the numeric code of the Char object passed to it. .NET Framework では、 Charオブジェクトは16ビット値です。In the .NET Framework, a Char object is a 16-bit value. つまり、メソッドは、ASCII 文字範囲内、または Unicode C0 コントロールと基本ラテン語の文字の数値コードを返すのに適しています。また、C1 コントロールと Latin-1 補完範囲 (U + 0000 から U + 00FF) にも対応しています。This means that the method is suitable for returning the numeric codes of characters in the ASCII character range or in the Unicode C0 Controls and Basic Latin, and C1 Controls and Latin-1 Supplement ranges, from U+0000 to U+00FF.

ToByte(DateTime) ToByte(DateTime) ToByte(DateTime) ToByte(DateTime)

このメソッドを呼び出すと、必ず InvalidCastException がスローされます。Calling this method always throws InvalidCastException.

public:
 static System::Byte ToByte(DateTime value);
public static byte ToByte (DateTime value);
static member ToByte : DateTime -> byte
Public Shared Function ToByte (value As DateTime) As Byte

パラメーター

value
DateTime DateTime DateTime DateTime

変換する日時の値。The date and time value to convert.

戻り値

この変換はサポートされていません。This conversion is not supported. 値は返されません。No value is returned.

例外

この変換はサポートされていません。This conversion is not supported.

ToByte(Boolean) ToByte(Boolean) ToByte(Boolean) ToByte(Boolean)

指定したブール値を等価の 8 ビット符号なし整数に変換します。Converts the specified Boolean value to the equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(bool value);
public static byte ToByte (bool value);
static member ToByte : bool -> byte
Public Shared Function ToByte (value As Boolean) As Byte

パラメーター

value
Boolean Boolean Boolean Boolean

変換するブール値。The Boolean value to convert.

戻り値

valuetrue の場合は数値の 1。それ以外の場合は 0。The number 1 if value is true; otherwise, 0.

次の例は、 Booleanを値に変換する方法をByte示しています。The following example illustrates the conversion of Boolean to Byte values.

using namespace System;

void main()
{
   bool falseFlag = false;
   bool trueFlag = true;

   Console::WriteLine("{0} converts to {1}.", falseFlag,
                      Convert::ToByte(falseFlag));
   Console::WriteLine("{0} converts to {1}.", trueFlag, 
                      Convert::ToByte(trueFlag));
}
// The example displays the following output:
//       False converts to 0.
//       True converts to 1.
bool falseFlag = false;
bool trueFlag = true;

Console.WriteLine("{0} converts to {1}.", falseFlag, 
                  Convert.ToByte(falseFlag));
Console.WriteLine("{0} converts to {1}.", trueFlag, 
                  Convert.ToByte(trueFlag));
// The example displays the following output:
//       False converts to 0.
//       True converts to 1.
Dim falseFlag As Boolean = False
Dim trueFlag As Boolean = True

Console.WriteLine("{0} converts to {1}.", falseFlag, _
                  Convert.ToByte(falseFlag))
Console.WriteLine("{0} converts to {1}.", trueFlag, _
                  Convert.ToByte(trueFlag))
' The example displays the following output:
'       False converts to 0.
'       True converts to 1.

ToByte(Int16) ToByte(Int16) ToByte(Int16) ToByte(Int16)

指定した 16 ビット符号付き整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 16-bit signed integer to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(short value);
public static byte ToByte (short value);
static member ToByte : int16 -> byte
Public Shared Function ToByte (value As Short) As Byte

パラメーター

value
Int16 Int16 Int16 Int16

変換する 16 ビット符号付き整数。The 16-bit signed integer to convert.

戻り値

value と等価の 8 ビット符号なし整数。An 8-bit unsigned integer that is equivalent to value.

例外

valueMinValue より小さいか MaxValue より大きいです。value is less than MinValue or greater than MaxValue.

次の例では、値Int16の配列Byteを値に変換します。The following example converts an array of Int16 values to Byte values.

short[] numbers = { Int16.MinValue, -1, 0, 121, 340, Int16.MaxValue };
byte result;
foreach (short number in numbers)
{
   try {
      result = Convert.ToByte(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", 
                        number.GetType().Name, number, 
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", 
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//       The Int16 value -32768 is outside the range of the Byte type.
//       The Int16 value -1 is outside the range of the Byte type.
//       Converted the Int16 value 0 to the Byte value 0.
//       Converted the Int16 value 121 to the Byte value 121.
//       The Int16 value 340 is outside the range of the Byte type.
//       The Int16 value 32767 is outside the range of the Byte type.
Dim numbers() As Short = { Int16.MinValue, -1, 0, 121, 340, Int16.MaxValue }
Dim result As Byte
For Each number As Short In numbers
   Try
      result = Convert.ToByte(number)
      Console.WriteLIne("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'       The Int16 value -32768 is outside the range of the Byte type.
'       The Int16 value -1 is outside the range of the Byte type.
'       Converted the Int16 value 0 to the Byte value 0.
'       Converted the Int16 value 121 to the Byte value 121.
'       The Int16 value 340 is outside the range of the Byte type.
'       The Int16 value 32767 is outside the range of the Byte type.

ToByte(Int32) ToByte(Int32) ToByte(Int32) ToByte(Int32)

指定した 32 ビット符号付き整数の値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified 32-bit signed integer to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(int value);
public static byte ToByte (int value);
static member ToByte : int -> byte
Public Shared Function ToByte (value As Integer) As Byte

パラメーター

value
Int32 Int32 Int32 Int32

変換する 32 ビット符号付き整数。The 32-bit signed integer to convert.

戻り値

value と等価の 8 ビット符号なし整数。An 8-bit unsigned integer that is equivalent to value.

例外

valueMinValue より小さいか MaxValue より大きいです。value is less than MinValue or greater than MaxValue.

次の例では、値Int32の配列Byteを値に変換します。The following example converts an array of Int32 values to Byte values.

int[] numbers = { Int32.MinValue, -1, 0, 121, 340, Int32.MaxValue };
byte result;
foreach (int number in numbers)
{
   try {
      result = Convert.ToByte(number);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", 
                        number.GetType().Name, number, 
                        result.GetType().Name, result);
   }                     
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", 
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//       The Int32 value -2147483648 is outside the range of the Byte type.
//       The Int32 value -1 is outside the range of the Byte type.
//       Converted the Int32 value 0 to the Byte value 0.
//       Converted the Int32 value 121 to the Byte value 121.
//       The Int32 value 340 is outside the range of the Byte type.
//       The Int32 value 2147483647 is outside the range of the Byte type.      
Dim numbers() As Integer = { Int32.MinValue, -1, 0, 121, 340, Int32.MaxValue }
Dim result As Byte
For Each number As Integer In numbers
   Try
      result = Convert.ToByte(number)
      Console.WriteLIne("Converted the {0} value {1} to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'       The Int32 value -2147483648 is outside the range of the Byte type.
'       The Int32 value -1 is outside the range of the Byte type.
'       Converted the Int32 value 0 to the Byte value 0.
'       Converted the Int32 value 121 to the Byte value 121.
'       The Int32 value 340 is outside the range of the Byte type.
'       The Int32 value 2147483647 is outside the range of the Byte type.      

ToByte(Decimal) ToByte(Decimal) ToByte(Decimal) ToByte(Decimal)

指定した 10 進数値を等価の 8 ビット符号なし整数に変換します。Converts the value of the specified decimal number to an equivalent 8-bit unsigned integer.

public:
 static System::Byte ToByte(System::Decimal value);
public static byte ToByte (decimal value);
static member ToByte : decimal -> byte
Public Shared Function ToByte (value As Decimal) As Byte

パラメーター

value
Decimal Decimal Decimal Decimal

変換する数値。The number to convert.

戻り値

近似値の 8 ビット符号なし整数に丸められた valuevalue, rounded to the nearest 8-bit unsigned integer. value が 2 つの整数のちょうど中間にある場合は、偶数が返されます。つまり、4.5 は 4 に変換され、5.5 は 6 に変換されます。If value is halfway between two whole numbers, the even number is returned; that is, 4.5 is converted to 4, and 5.5 is converted to 6.

例外

valueMaxValue を超えているか、または MinValue 未満です。value is greater than MaxValue or less than MinValue.

注釈

次の例ではByte 、値Decimal Decimalをに変換し、値Byteをに変換します。The following example converts a Byte value to a Decimal and a Decimal value to a Byte.

public:
   void ConvertByteDecimal( Byte byteVal )
   {
      Decimal decimalVal;
      
      // Byte to decimal conversion will not overflow.
      decimalVal = System::Convert::ToDecimal( byteVal );
      System::Console::WriteLine( "The Byte as a decimal is {0}.",
         decimalVal );
      
      // Decimal to Byte conversion can overflow.
      try
      {
         byteVal = System::Convert::ToByte( decimalVal );
         System::Console::WriteLine( "The Decimal as a Byte is {0}.",
         byteVal );
      }
      catch ( System::OverflowException^ ) 
      {
         System::Console::WriteLine(
            "The decimal value is too large for a Byte." );
      }
   }
public void ConvertByteDecimal(byte byteVal) {
	decimal decimalVal;

	// Byte to decimal conversion will not overflow.
	decimalVal = System.Convert.ToDecimal(byteVal);
	System.Console.WriteLine("The byte as a decimal is {0}.",
		decimalVal);

	// Decimal to byte conversion can overflow.
	try {
		byteVal = System.Convert.ToByte(decimalVal);
		System.Console.WriteLine("The Decimal as a byte is {0}.",
			byteVal);
	}
	catch (System.OverflowException) {
		System.Console.WriteLine(
			"The decimal value is too large for a byte.");
	}
}
Public Sub ConvertByteDecimal(ByVal byteVal As Byte)
    Dim decimalVal As Decimal

    ' Byte to decimal conversion will not overflow.
    decimalVal = System.Convert.ToDecimal(byteVal)
    System.Console.WriteLine("The byte as a decimal is {0}.", _
                              decimalVal)

    ' Decimal to byte conversion can overflow.
    Try
        byteVal = System.Convert.ToByte(decimalVal)
        System.Console.WriteLine("The Decimal as a byte is {0}.", _
                                  byteVal)
    Catch exception As System.OverflowException
        System.Console.WriteLine( _
            "Overflow in decimal-to-byte conversion.")
    End Try
End Sub

ToByte(Object) ToByte(Object) ToByte(Object) ToByte(Object)

指定したオブジェクトの値を 8 ビット符号なし整数に変換します。Converts the value of the specified object to an 8-bit unsigned integer.

public:
 static System::Byte ToByte(System::Object ^ value);
public static byte ToByte (object value);
static member ToByte : obj -> byte
Public Shared Function ToByte (value As Object) As Byte

パラメーター

value
Object Object Object Object

IConvertible インターフェイスを実装するオブジェクトか、または nullAn object that implements the IConvertible interface, or null.

戻り値

value と等価の 8 ビット符号なし整数。valuenull の場合は 0。An 8-bit unsigned integer that is equivalent to value, or zero if value is null.

例外

valueByte 値のプロパティの形式ではありません。value is not in the property format for a Byte value.

valueIConvertible を実装していません。value does not implement IConvertible.

- または --or- value から Byte 型への変換はサポートされていません。Conversion from value to the Byte type is not supported.

valueMinValue 未満の数値か、MaxValue より大きい数値を表します。value represents a number that is less than MinValue or greater than MaxValue.

次の例ではToByte(Object) 、メソッドを使用して、オブジェクトByteの配列を値に変換します。The following example uses the ToByte(Object) method to convert an array of objects to Byte values.

object[] values = { true, -12, 163, 935, 'x', "104", "103.0", "-1", 
                    "1.00e2", "One", 1.00e2};
byte result;
foreach (object value in values)
{
   try {
      result = Convert.ToByte(value);
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", 
                        value.GetType().Name, value, 
                        result.GetType().Name, result);
   }                     
   catch (OverflowException)
   {
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", 
                        value.GetType().Name, value);
   }                     
   catch (FormatException)
   {
      Console.WriteLine("The {0} value {1} is not in a recognizable format.", 
                        value.GetType().Name, value);
   }
   catch (InvalidCastException)
   {
      Console.WriteLine("No conversion to a Byte exists for the {0} value {1}.", 
                        value.GetType().Name, value);
                        
   }
}                           
// The example displays the following output:
//       Converted the Boolean value True to the Byte value 1.
//       The Int32 value -12 is outside the range of the Byte type.
//       Converted the Int32 value 163 to the Byte value 163.
//       The Int32 value 935 is outside the range of the Byte type.
//       Converted the Char value x to the Byte value 120.
//       Converted the String value 104 to the Byte value 104.
//       The String value 103.0 is not in a recognizable format.
//       The String value -1 is outside the range of the Byte type.
//       The String value 1.00e2 is not in a recognizable format.
//       The String value One is not in a recognizable format.
//       Converted the Double value 100 to the Byte value 100.      
Dim values() As Object = { True, -12, 163, 935, "x"c, "104", "103.0", "-1", _
                           "1.00e2", "One", 1.00e2}
Dim result As Byte
For Each value As Object In values
   Try
      result = Convert.ToByte(value)
      Console.WriteLine("Converted the {0} value {1} to the {2} value {3}.", _
                        value.GetType().Name, value, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the Byte type.", _
                        value.GetType().Name, value)
   Catch e As FormatException
      Console.WriteLine("The {0} value {1} is not in a recognizable format.", _
                        value.GetType().Name, value)
   Catch e As InvalidCastException
      Console.WriteLine("No conversion to a Byte exists for the {0} value {1}.", _
                        value.GetType().Name, value)
                        
   End Try
Next                           
' The example displays the following output:
'       Converted the Boolean value True to the Byte value 1.
'       The Int32 value -12 is outside the range of the Byte type.
'       Converted the Int32 value 163 to the Byte value 163.
'       The Int32 value 935 is outside the range of the Byte type.
'       Converted the Char value x to the Byte value 120.
'       Converted the String value 104 to the Byte value 104.
'       The String value 103.0 is not in a recognizable format.
'       The String value -1 is outside the range of the Byte type.
'       The String value 1.00e2 is not in a recognizable format.
'       The String value One is not in a recognizable format.
'       Converted the Double value 100 to the Byte value 100.      

注釈

valueでないnull場合、このメソッドは、のvalueIConvertible.ToByteになる型の実装への呼び出しをラップします。If value is not null, this method wraps a call to the IConvertible.ToByte implementation of the underlying type of value.

適用対象