Int32.Parse 方法

定義

將數字的字串表示轉換成它的對等 32 位元帶正負號的整數。Converts the string representation of a number to its 32-bit signed integer equivalent.

多載

Parse(String, NumberStyles, IFormatProvider)

將指定樣式和特定文化特性格式之數字的字串表示轉換成它的對等 32 位元帶正負號的整數。Converts the string representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent.

Parse(ReadOnlySpan<Char>, NumberStyles, IFormatProvider)

將數字的範圍表示 (使用指定樣式和特定文化特性格式) 轉換為其對等 32 位元帶正負號的整數。Converts the span representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent.

Parse(String, NumberStyles)

將指定樣式之數字的字串表示轉換成它的對等 32 位元帶正負號的整數。Converts the string representation of a number in a specified style to its 32-bit signed integer equivalent.

Parse(String)

將數字的字串表示轉換成它的對等 32 位元帶正負號的整數。Converts the string representation of a number to its 32-bit signed integer equivalent.

Parse(String, IFormatProvider)

將指定特定文化特性格式之數字的字串表示轉換成它的對等 32 位元帶正負號的整數。Converts the string representation of a number in a specified culture-specific format to its 32-bit signed integer equivalent.

Parse(String, NumberStyles, IFormatProvider)

將指定樣式和特定文化特性格式之數字的字串表示轉換成它的對等 32 位元帶正負號的整數。Converts the string representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent.

public:
 static int Parse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider);
public static int Parse (string s, System.Globalization.NumberStyles style, IFormatProvider provider);
static member Parse : string * System.Globalization.NumberStyles * IFormatProvider -> int
Public Shared Function Parse (s As String, style As NumberStyles, provider As IFormatProvider) As Integer

參數

s
String

字串,包含要轉換的數字。A string containing a number to convert.

style
NumberStyles

列舉值的位元組合,表示 s 中可以存在的樣式項目。A bitwise combination of enumeration values that indicates the style elements that can be present in s. 一般會指定的值是 IntegerA typical value to specify is Integer.

provider
IFormatProvider

物件,提供 s 格式的相關特定文化特性資訊。An object that supplies culture-specific information about the format of s.

傳回

32 位元帶正負號的整數,與 s 中所指定的數字相等。A 32-bit signed integer equivalent to the number specified in s.

例外狀況

snulls is null.

style 不是 NumberStyles 值。style is not a NumberStyles value.

-或--or- style 不是 AllowHexSpecifierHexNumber 值的組合。style is not a combination of AllowHexSpecifier and HexNumber values.

s 的格式與 style 不相容。s is not in a format compliant with style.

s 代表小於 MinValue 或大於 MaxValue 的數字。s represents a number less than MinValue or greater than MaxValue.

-或--or- s 包含非零的小數數字。s includes non-zero, fractional digits.

範例

下列範例會使用各種 styleprovider 參數來剖析 Int32 值的字串表示。The following example uses a variety of style and provider parameters to parse the string representations of Int32 values. 它也說明了一些不同的方式,可以根據用於剖析作業之格式資訊的文化特性來解讀相同的字串。It also illustrates some of the different ways the same string can be interpreted depending on the culture whose formatting information is used for the parsing operation.

using namespace System;
using namespace System::Globalization;

public ref class ParseInt32
{
public:
   static void Main()
   {
      Convert("12,000", NumberStyles::Float | NumberStyles::AllowThousands, 
              gcnew CultureInfo("en-GB"));
      Convert("12,000", NumberStyles::Float | NumberStyles::AllowThousands,
              gcnew CultureInfo("fr-FR"));
      Convert("12,000", NumberStyles::Float, gcnew CultureInfo("en-US"));

      Convert("12 425,00", NumberStyles::Float | NumberStyles::AllowThousands,
              gcnew CultureInfo("sv-SE"));
      Convert("12,425.00", NumberStyles::Float | NumberStyles::AllowThousands,
              NumberFormatInfo::InvariantInfo);
      Convert("631,900", NumberStyles::Integer | NumberStyles::AllowDecimalPoint, 
              gcnew CultureInfo("fr-FR"));
      Convert("631,900", NumberStyles::Integer | NumberStyles::AllowDecimalPoint,
              gcnew CultureInfo("en-US"));
      Convert("631,900", NumberStyles::Integer | NumberStyles::AllowThousands,
              gcnew CultureInfo("en-US"));
   }

private:
   static void Convert(String^ value, NumberStyles style,
                               IFormatProvider^ provider)
   {
      try
      {
         int number = Int32::Parse(value, style, provider);
         Console::WriteLine("Converted '{0}' to {1}.", value, number);
      }
      catch (FormatException^)
      {
         Console::WriteLine("Unable to convert '{0}'.", value);
      }
      catch (OverflowException^)
      {
         Console::WriteLine("'{0}' is out of range of the Int32 type.", value);   
      }
   }                               
};

int main()
{
    ParseInt32::Main();
}
// This example displays the following output to the console:
//       Converted '12,000' to 12000.
//       Converted '12,000' to 12.
//       Unable to convert '12,000'.
//       Converted '12 425,00' to 12425.
//       Converted '12,425.00' to 12425.
//       '631,900' is out of range of the Int32 type.
//       Unable to convert '631,900'.
//       Converted '631,900' to 631900.
using System;
using System.Globalization;

public class ParseInt32
{
   public static void Main()
   {
      Convert("12,000", NumberStyles.Float | NumberStyles.AllowThousands, 
              new CultureInfo("en-GB"));
      Convert("12,000", NumberStyles.Float | NumberStyles.AllowThousands,
              new CultureInfo("fr-FR"));
      Convert("12,000", NumberStyles.Float, new CultureInfo("en-US"));
      
      Convert("12 425,00", NumberStyles.Float | NumberStyles.AllowThousands,
              new CultureInfo("sv-SE"));
      Convert("12,425.00", NumberStyles.Float | NumberStyles.AllowThousands,
              NumberFormatInfo.InvariantInfo);
      Convert("631,900", NumberStyles.Integer | NumberStyles.AllowDecimalPoint, 
              new CultureInfo("fr-FR"));
      Convert("631,900", NumberStyles.Integer | NumberStyles.AllowDecimalPoint,
              new CultureInfo("en-US"));
      Convert("631,900", NumberStyles.Integer | NumberStyles.AllowThousands,
              new CultureInfo("en-US"));
   }

   private static void Convert(string value, NumberStyles style, 
                               IFormatProvider provider)
   {
      try
      {
         int number = Int32.Parse(value, style, provider);
         Console.WriteLine("Converted '{0}' to {1}.", value, number);
      }
      catch (FormatException)
      {
         Console.WriteLine("Unable to convert '{0}'.", value);
      }   
      catch (OverflowException)
      {
         Console.WriteLine("'{0}' is out of range of the Int32 type.", value);   
      }
   }                               
}
// This example displays the following output to the console:
//       Converted '12,000' to 12000.
//       Converted '12,000' to 12.
//       Unable to convert '12,000'.
//       Converted '12 425,00' to 12425.
//       Converted '12,425.00' to 12425.
//       '631,900' is out of range of the Int32 type.
//       Unable to convert '631,900'.
//       Converted '631,900' to 631900.
Imports System.Globalization

Module ParseInt32
   Public Sub Main()
      Convert("12,000", NumberStyles.Float Or NumberStyles.AllowThousands, _
              New CultureInfo("en-GB"))      
      Convert("12,000", NumberStyles.Float Or NumberStyles.AllowThousands, _
              New CultureInfo("fr-FR"))
      Convert("12,000", NumberStyles.Float, New CultureInfo("en-US"))
      
      Convert("12 425,00", NumberStyles.Float Or NumberStyles.AllowThousands, _
              New CultureInfo("sv-SE")) 
      Convert("12,425.00", NumberStyles.Float Or NumberStyles.AllowThousands, _
              NumberFormatInfo.InvariantInfo) 
      Convert("631,900", NumberStyles.Integer Or NumberStyles.AllowDecimalPoint, _ 
              New CultureInfo("fr-FR"))
      Convert("631,900", NumberStyles.Integer Or NumberStyles.AllowDecimalPoint, _
              New CultureInfo("en-US"))
      Convert("631,900", NumberStyles.Integer Or NumberStyles.AllowThousands, _
              New CultureInfo("en-US"))
   End Sub

   Private Sub Convert(value As String, style As NumberStyles, _
                       provider As IFormatProvider)
      Try
         Dim number As Integer = Int32.Parse(value, style, provider)
         Console.WriteLine("Converted '{0}' to {1}.", value, number)
      Catch e As FormatException
         Console.WriteLine("Unable to convert '{0}'.", value)
      Catch e As OverflowException
         Console.WriteLine("'{0}' is out of range of the Int32 type.", value)   
      End Try
   End Sub                       
End Module
' This example displays the following output to the console:
'       Converted '12,000' to 12000.
'       Converted '12,000' to 12.
'       Unable to convert '12,000'.
'       Converted '12 425,00' to 12425.
'       Converted '12,425.00' to 12425.
'       '631,900' is out of range of the Int32 type.
'       Unable to convert '631,900'.
'       Converted '631,900' to 631900.

備註

style 參數會定義在 s 參數中允許的樣式元素(例如空白字元或正號),使剖析作業成功。The style parameter defines the style elements (such as white space or the positive sign) that are allowed in the s parameter for the parse operation to succeed. 它必須是來自 NumberStyles 列舉的位旗標組合。It must be a combination of bit flags from the NumberStyles enumeration. 根據 style的值,s 參數可能包含下列元素:Depending on the value of style, the s parameter may include the following elements:

atl-ws-01[$]簽訂[數位,] 數位 [. fractional_digist] [e [sign] exponential_digits] [ws][ws][$][sign][digits,]digits[.fractional_digist][e[sign]exponential_digits][ws]

或者,如果 style 包含 AllowHexSpecifierOr, if style includes AllowHexSpecifier:

[ws] hexdigits [ws][ws]hexdigits[ws]

以方括弧([和])括住的專案是選擇性的。Items in square brackets ([ and ]) are optional. 下表說明每個元素。The following table describes each element.

項目Element 說明Description
wsws 選擇性的空白字元。Optional white space. 如果 style 包含 NumberStyles.AllowLeadingWhite 旗標,則空格可以出現在 s 的開頭,如果 style 包含 NumberStyles.AllowTrailingWhite 旗標,它可以出現在 s 的結尾。White space can appear at the beginning of s if style includes the NumberStyles.AllowLeadingWhite flag, and it can appear at the end of s if style includes the NumberStyles.AllowTrailingWhite flag.
$ 特定文化特性的貨幣符號。A culture-specific currency symbol. 其在字串中的位置是由 provider 參數的 GetFormat 方法所傳回之 NumberFormatInfo 物件的 NumberFormatInfo.CurrencyPositivePattern 屬性所定義。Its position in the string is defined by the NumberFormatInfo.CurrencyPositivePattern property of the NumberFormatInfo object returned by the GetFormat method of the provider parameter. 如果 style 包含 NumberStyles.AllowCurrencySymbol 旗標,貨幣符號可能會出現在 s 中。The currency symbol can appear in s if style includes the NumberStyles.AllowCurrencySymbol flag.
簽署sign 選擇性的正負號。An optional sign. 如果 style 包含 NumberStyles.AllowTrailingSign 旗標,則符號會出現在 s 開頭(如果 style 包含 NumberStyles.AllowLeadingSign 旗標或 s 結尾)。The sign can appear at the beginning of s if style includes the NumberStyles.AllowLeadingSign flag or at the end of s if style includes the NumberStyles.AllowTrailingSign flag. 如果 style 包含 NumberStyles.AllowParentheses 旗標,則可以在 s 中使用括弧來表示負數值。Parentheses can be used in s to indicate a negative value if style includes the NumberStyles.AllowParentheses flag.
digitsdigits

fractional_digitsfractional_digits

exponential_digitsexponential_digits
從0到9的數位序列。A sequence of digits from 0 through 9. 針對fractional_digits,只有數位0是有效的。For fractional_digits, only the digit 0 is valid.
, 文化特性特定的千位分隔符號。A culture-specific thousands separator symbol. 如果 style 包含 NumberStyles.AllowThousands 旗標,provider 所指定之文化特性的千位分隔符號會出現在 s 中。The thousands separator of the culture specified by provider can appear in s if style includes the NumberStyles.AllowThousands flag.
.. 文化特性特定的小數點符號。A culture-specific decimal point symbol. 如果 style 包含 NumberStyles.AllowDecimalPoint 旗標,provider 所指定文化特性的小數點符號會出現在 s 中。The decimal point symbol of the culture specified by provider can appear in s if style includes the NumberStyles.AllowDecimalPoint flag.

只有數位0可以顯示為小數位數,剖析作業才會成功;如果fractional_digits包含任何其他數位,則會擲回 OverflowExceptionOnly the digit 0 can appear as a fractional digit for the parse operation to succeed; if fractional_digits includes any other digit, an OverflowException is thrown.
ee ' E ' 或 ' E ' 字元,表示該值是以指數標記法表示。The 'e' or 'E' character, which indicates that the value is represented in exponential notation. 如果 style 包含 NumberStyles.AllowExponent 旗標,s 參數可以表示指數標記法中的數位。The s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.
hexdigitshexdigits 從0到 f 的十六進位數位序列,或0到 F。A sequence of hexadecimal digits from 0 through f, or 0 through F.

注意

不論 style 引數的值為何,剖析作業都會忽略 s 中的任何終止 NUL (U + 0000)字元。Any terminating NUL (U+0000) characters in s are ignored by the parsing operation, regardless of the value of the style argument.

只有十進位數的字串(對應至 NumberStyles.None 樣式)一律會在 Int32 類型的範圍內成功剖析。A string with decimal digits only (which corresponds to the NumberStyles.None style) always parses successfully if it is in the range of the Int32 type. 大部分的其餘 NumberStyles 成員控制元素,這些專案可能是但不需要出現在此輸入字串中。Most of the remaining NumberStyles members control elements that may be but are not required to be present in this input string. 下表指出個別 NumberStyles 成員如何影響 s中可能存在的元素。The following table indicates how individual NumberStyles members affect the elements that may be present in s.

非複合 NumberStyles 值Non-composite NumberStyles values 除了數位之外,s 中允許的元素Elements permitted in s in addition to digits
NumberStyles.None 僅限十進位數。Decimal digits only.
NumberStyles.AllowDecimalPoint 小數點( .The decimal point ( . )和小數位數元素。) and fractional-digits elements. 不過,小數數位只能包含一或多個0位數,或擲回 OverflowExceptionHowever, fractional-digits must consist of only one or more 0 digits or an OverflowException is thrown.
NumberStyles.AllowExponent s 參數也可以使用指數標記法。The s parameter can also use exponential notation. 如果 s 代表指數標記法中的數位,則必須代表不含非零小陣列件的 Int32 資料類型範圍內的整數。If s represents a number in exponential notation, it must represent an integer within the range of the Int32 data type without a non-zero, fractional component.
NumberStyles.AllowLeadingWhite s開頭的ws元素。The ws element at the beginning of s.
NumberStyles.AllowTrailingWhite s結尾的ws元素。The ws element at the end of s.
NumberStyles.AllowLeadingSign 正號可以出現在數位前面。A positive sign can appear before digits.
NumberStyles.AllowTrailingSign 正號可以在數位之後出現。A positive sign can appear after digits.
NumberStyles.AllowParentheses 以括弧形式括住數值的sign元素。The sign element in the form of parentheses enclosing the numeric value.
NumberStyles.AllowThousands 千位分隔符號( )元素。The thousands separator ( , ) element.
NumberStyles.AllowCurrencySymbol $ 元素。The $ element.

如果使用 NumberStyles.AllowHexSpecifier 旗標,s 必須是不含前置詞的十六進位值。If the NumberStyles.AllowHexSpecifier flag is used, s must be a hexadecimal value without a prefix. 例如,"C9AF3" 會成功剖析,但 "0xC9AF3" 則不會。For example, "C9AF3" parses successfully, but "0xC9AF3" does not. style 中唯一可以出現的其他旗標是 NumberStyles.AllowLeadingWhiteNumberStyles.AllowTrailingWhiteThe only other flags that can be present in style are NumberStyles.AllowLeadingWhite and NumberStyles.AllowTrailingWhite. NumberStyles 列舉具有複合數位樣式,NumberStyles.HexNumber,其中同時包含空白字元旗標)。(The NumberStyles enumeration has a composite number style, NumberStyles.HexNumber, that includes both white space flags.)

provider 參數是 IFormatProvider 的執行,例如 NumberFormatInfoCultureInfo 物件。The provider parameter is an IFormatProvider implementation, such as a NumberFormatInfo or CultureInfo object. provider 參數提供用於剖析的特定文化特性資訊。The provider parameter supplies culture-specific information used in parsing. 如果 null``provider,則會使用目前文化特性的 NumberFormatInfo 物件。If provider is null, the NumberFormatInfo object for the current culture is used.

另請參閱

Parse(ReadOnlySpan<Char>, NumberStyles, IFormatProvider)

將數字的範圍表示 (使用指定樣式和特定文化特性格式) 轉換為其對等 32 位元帶正負號的整數。Converts the span representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent.

public static int Parse (ReadOnlySpan<char> s, System.Globalization.NumberStyles style = System.Globalization.NumberStyles.Integer, IFormatProvider provider = null);
static member Parse : ReadOnlySpan<char> * System.Globalization.NumberStyles * IFormatProvider -> int
Public Shared Function Parse (s As ReadOnlySpan(Of Char), Optional style As NumberStyles = System.Globalization.NumberStyles.Integer, Optional provider As IFormatProvider = null) As Integer

參數

s
ReadOnlySpan<Char>

範圍,其包含代表所要轉換數字的字元。A span containing the characters representing the number to convert.

style
NumberStyles

列舉值的位元組合,表示 s 中可以存在的樣式項目。A bitwise combination of enumeration values that indicates the style elements that can be present in s. 一般會指定的值是 IntegerA typical value to specify is Integer.

provider
IFormatProvider

物件,提供 s 格式的相關特定文化特性資訊。An object that supplies culture-specific information about the format of s.

傳回

32 位元帶正負號的整數,與 s 中所指定的數字相等。A 32-bit signed integer equivalent to the number specified in s.

Parse(String, NumberStyles)

將指定樣式之數字的字串表示轉換成它的對等 32 位元帶正負號的整數。Converts the string representation of a number in a specified style to its 32-bit signed integer equivalent.

public:
 static int Parse(System::String ^ s, System::Globalization::NumberStyles style);
public static int Parse (string s, System.Globalization.NumberStyles style);
static member Parse : string * System.Globalization.NumberStyles -> int
Public Shared Function Parse (s As String, style As NumberStyles) As Integer

參數

s
String

字串,包含要轉換的數字。A string containing a number to convert.

style
NumberStyles

列舉值的位元組合,表示 s 中可以存在的樣式項目。A bitwise combination of the enumeration values that indicates the style elements that can be present in s. 一般會指定的值是 IntegerA typical value to specify is Integer.

傳回

32 位元帶正負號的整數,與 s 中所指定的數字相等。A 32-bit signed integer equivalent to the number specified in s.

例外狀況

snulls is null.

style 不是 NumberStyles 值。style is not a NumberStyles value.

-或--or- style 不是 AllowHexSpecifierHexNumber 值的組合。style is not a combination of AllowHexSpecifier and HexNumber values.

s 的格式與 style 不相容。s is not in a format compliant with style.

s 代表小於 MinValue 或大於 MaxValue 的數字。s represents a number less than MinValue or greater than MaxValue.

-或--or- s 包含非零的小數數字。s includes non-zero, fractional digits.

範例

下列範例會使用 Int32.Parse(String, NumberStyles) 方法來剖析數個 Int32 值的字串表示。The following example uses the Int32.Parse(String, NumberStyles) method to parse the string representations of several Int32 values. 此範例的目前文化特性為 en-us。The current culture for the example is en-US.

using namespace System;
using namespace System::Globalization;

public ref class ParseInt32
{
public:
   static void Main()
   {
      Convert("104.0", NumberStyles::AllowDecimalPoint);
      Convert("104.9", NumberStyles::AllowDecimalPoint);
      Convert(" $17,198,064.42", NumberStyles::AllowCurrencySymbol |
                                 NumberStyles::Number);
      Convert("103E06", NumberStyles::AllowExponent);
      Convert("-1,345,791", NumberStyles::AllowThousands);
      Convert("(1,345,791)", NumberStyles::AllowThousands |
                             NumberStyles::AllowParentheses);
   }

private:
   static void Convert(String^ value, NumberStyles style)
   {
      try
      {
         int number = Int32::Parse(value, style);
         Console::WriteLine("Converted '{0}' to {1}.", value, number);
      }
      catch (FormatException^)
      {
         Console::WriteLine("Unable to convert '{0}'.", value);
      }
      catch (OverflowException^)
      {
         Console::WriteLine("'{0}' is out of range of the Int32 type.", value);
      }
   }
};

int main()
{
    ParseInt32::Main();
}
// The example displays the following output to the console:
//       Converted '104.0' to 104.
//       '104.9' is out of range of the Int32 type.
//       ' $17,198,064.42' is out of range of the Int32 type.
//       Converted '103E06' to 103000000.
//       Unable to convert '-1,345,791'.
//       Converted '(1,345,791)' to -1345791.
using System;
using System.Globalization;

public class ParseInt32
{
   public static void Main()
   {
      Convert("104.0", NumberStyles.AllowDecimalPoint);
      Convert("104.9", NumberStyles.AllowDecimalPoint);
      Convert(" $17,198,064.42", NumberStyles.AllowCurrencySymbol |
                                 NumberStyles.Number);
      Convert("103E06", NumberStyles.AllowExponent);
      Convert("-1,345,791", NumberStyles.AllowThousands);
      Convert("(1,345,791)", NumberStyles.AllowThousands |
                             NumberStyles.AllowParentheses);
   }

   private static void Convert(string value, NumberStyles style)
   {
      try
      {
         int number = Int32.Parse(value, style);
         Console.WriteLine("Converted '{0}' to {1}.", value, number);
      }
      catch (FormatException)
      {
         Console.WriteLine("Unable to convert '{0}'.", value);
      }
      catch (OverflowException)
      {
         Console.WriteLine("'{0}' is out of range of the Int32 type.", value);   
      }
   }
}
// The example displays the following output to the console:
//       Converted '104.0' to 104.
//       '104.9' is out of range of the Int32 type.
//       ' $17,198,064.42' is out of range of the Int32 type.
//       Converted '103E06' to 103000000.
//       Unable to convert '-1,345,791'.
//       Converted '(1,345,791)' to -1345791.
Imports System.Globalization

Module ParseInt32
   Public Sub Main()
      Convert("104.0", NumberStyles.AllowDecimalPoint)    
      Convert("104.9", NumberStyles.AllowDecimalPoint)
      Convert(" $17,198,064.42", NumberStyles.AllowCurrencySymbol Or _
                                 NumberStyles.Number)
      Convert("103E06", NumberStyles.AllowExponent)  
      Convert("-1,345,791", NumberStyles.AllowThousands)
      Convert("(1,345,791)", NumberStyles.AllowThousands Or _
                             NumberStyles.AllowParentheses)
   End Sub
   
   Private Sub Convert(value As String, style As NumberStyles)
      Try
         Dim number As Integer = Int32.Parse(value, style)
         Console.WriteLine("Converted '{0}' to {1}.", value, number)
      Catch e As FormatException
         Console.WriteLine("Unable to convert '{0}'.", value)
      Catch e As OverflowException
         Console.WriteLine("'{0}' is out of range of the Int32 type.", value)   
      End Try
   End Sub
End Module
' The example displays the following output to the console:
'       Converted '104.0' to 104.
'       '104.9' is out of range of the Int32 type.
'       ' $17,198,064.42' is out of range of the Int32 type.
'       Converted '103E06' to 103000000.
'       Unable to convert '-1,345,791'.
'       Converted '(1,345,791)' to -1345791.

備註

style 參數會定義要成功進行剖析作業的 s 參數所允許的樣式元素(例如空白字元、正數或負號符號,或千位分隔符號)。The style parameter defines the style elements (such as white space, the positive or negative sign symbol, or the thousands separator symbol) that are allowed in the s parameter for the parse operation to succeed. 它必須是來自 NumberStyles 列舉的位旗標組合。It must be a combination of bit flags from the NumberStyles enumeration. 根據 style的值,s 參數可能包含下列元素:Depending on the value of style, the s parameter may include the following elements:

[ws][$][sign][digits,]digits[.fractional_digits][e[sign]exponential_digits][ws][ws][$][sign][digits,]digits[.fractional_digits][e[sign]exponential_digits][ws]

或者,如果 style 包含 AllowHexSpecifierOr, if style includes AllowHexSpecifier:

[ws] hexdigits [ws][ws]hexdigits[ws]

以方括弧([和])括住的專案是選擇性的。Items in square brackets ([ and ]) are optional. 下表說明每個元素。The following table describes each element.

項目Element 說明Description
wsws 選擇性的空白字元。Optional white space. 如果 style 包含 NumberStyles.AllowLeadingWhite 旗標,則空格可以出現在 s 的開頭,如果 style 包含 NumberStyles.AllowTrailingWhite 旗標,它可以出現在 s 的結尾。White space can appear at the beginning of s if style includes the NumberStyles.AllowLeadingWhite flag, and it can appear at the end of s if style includes the NumberStyles.AllowTrailingWhite flag.
$ 特定文化特性的貨幣符號。A culture-specific currency symbol. 其在字串中的位置是由目前文化特性的 NumberFormatInfo.CurrencyNegativePatternNumberFormatInfo.CurrencyPositivePattern 屬性所定義。Its position in the string is defined by the NumberFormatInfo.CurrencyNegativePattern and NumberFormatInfo.CurrencyPositivePattern properties of the current culture. 如果 style 包含 NumberStyles.AllowCurrencySymbol 旗標,則目前文化特性的貨幣符號可能會出現在 s 中。The current culture's currency symbol can appear in s if style includes the NumberStyles.AllowCurrencySymbol flag.
簽署sign 選擇性的正負號。An optional sign. 如果 style 包含 NumberStyles.AllowLeadingSign 旗標,則正負號可以出現在 s 的開頭,如果 style 包含 NumberStyles.AllowTrailingSign 旗標,它可以出現在 s 的結尾。The sign can appear at the beginning of s if style includes the NumberStyles.AllowLeadingSign flag, and it can appear at the end of s if style includes the NumberStyles.AllowTrailingSign flag. 如果 style 包含 NumberStyles.AllowParentheses 旗標,則可以在 s 中使用括弧來表示負數值。Parentheses can be used in s to indicate a negative value if style includes the NumberStyles.AllowParentheses flag.
digitsdigits

fractional_digitsfractional_digits

exponential_digitsexponential_digits
從0到9的數位序列。A sequence of digits from 0 through 9. 針對fractional_digits,只有數位0是有效的。For fractional_digits, only the digit 0 is valid.
, 文化特性特定的千位分隔符號。A culture-specific thousands separator symbol. 如果 style 包含 NumberStyles.AllowThousands 旗標,則目前文化特性的千位分隔符號可能會出現在 s 中。The current culture's thousands separator can appear in s if style includes the NumberStyles.AllowThousands flag.
.. 文化特性特定的小數點符號。A culture-specific decimal point symbol. 如果 style 包含 NumberStyles.AllowDecimalPoint 旗標,則目前文化特性的小數點符號可能會出現在 s 中。The current culture's decimal point symbol can appear in s if style includes the NumberStyles.AllowDecimalPoint flag. 只有數位0可以顯示為小數位數,剖析作業才會成功;如果fractional_digits包含任何其他數位,則會擲回 OverflowExceptionOnly the digit 0 can appear as a fractional digit for the parse operation to succeed; if fractional_digits includes any other digit, an OverflowException is thrown.
ee ' E ' 或 ' E ' 字元,表示該值是以指數標記法表示。The 'e' or 'E' character, which indicates that the value is represented in exponential notation. 如果 style 包含 NumberStyles.AllowExponent 旗標,s 參數可以表示指數標記法中的數位。The s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.
hexdigitshexdigits 從0到 f 的十六進位數位序列,或0到 F。A sequence of hexadecimal digits from 0 through f, or 0 through F.

注意

不論 style 引數的值為何,剖析作業都會忽略 s 中的任何終止 NUL (U + 0000)字元。Any terminating NUL (U+0000) characters in s are ignored by the parsing operation, regardless of the value of the style argument.

只有數位(對應至 NumberStyles.None 樣式)的字串如果在 Int32 類型的範圍內,一律會剖析成功。A string with digits only (which corresponds to the NumberStyles.None style) always parses successfull if it is in the range of the Int32 type. 大部分的其餘 NumberStyles 成員控制元素,這些專案可能是但不需要出現在輸入字串中。Most of the remaining NumberStyles members control elements that may be but are not required to be present in the input string. 下表指出個別 NumberStyles 成員如何影響 s中可能存在的元素。The following table indicates how individual NumberStyles members affect the elements that may be present in s.

NumberStyles 值NumberStyles value 除了數位之外,s 中允許的元素Elements permitted in s in addition to digits
None 僅限數位元素。The digits element only.
AllowDecimalPoint 小數點( .The decimal point ( . )和小數位數元素。) and fractional-digits elements.
AllowExponent s 參數也可以使用指數標記法。The s parameter can also use exponential notation.
AllowLeadingWhite s開頭的ws元素。The ws element at the beginning of s.
AllowTrailingWhite s結尾的ws元素。The ws element at the end of s.
AllowLeadingSign s開頭的sign元素。The sign element at the beginning of s.
AllowTrailingSign s結尾的sign元素。The sign element at the end of s.
AllowParentheses 以括弧形式括住數值的sign元素。The sign element in the form of parentheses enclosing the numeric value.
AllowThousands 千位分隔符號( )元素。The thousands separator ( , ) element.
AllowCurrencySymbol $ 元素。The $ element.
Currency 全部。All. s 參數不能以指數標記法表示十六進位數位或數位。The s parameter cannot represent a hexadecimal number or a number in exponential notation.
Float s開頭或結尾處的ws元素、s開頭的符號,以及小數點( .The ws element at the beginning or end of s, sign at the beginning of s, and the decimal point ( . 百分號.) symbol. s 參數也可以使用指數標記法。The s parameter can also use exponential notation.
Number wssign、千位分隔符號( )和小數點( .The ws, sign, thousands separator ( , ), and decimal point ( . 要素.) elements.
Any 除了 s 以外的所有樣式都不能代表十六進位數位。All styles, except s cannot represent a hexadecimal number.

如果使用 NumberStyles.AllowHexSpecifier 旗標,s 必須是不含前置詞的十六進位值。If the NumberStyles.AllowHexSpecifier flag is used, s must be a hexadecimal value without a prefix. 例如,"C9AF3" 會成功剖析,但 "0xC9AF3" 則不會。For example, "C9AF3" parses successfully, but "0xC9AF3" does not. 唯一可與 s 參數結合 NumberStyles.AllowLeadingWhiteNumberStyles.AllowTrailingWhite的其他旗標。The only other flags that can be combined with the s parameter it are NumberStyles.AllowLeadingWhite and NumberStyles.AllowTrailingWhite. NumberStyles 列舉包含複合數位樣式,NumberStyles.HexNumber,其中同時包含空白字元旗標)。(The NumberStyles enumeration includes a composite number style, NumberStyles.HexNumber, that includes both white space flags.)

s 參數會使用針對目前系統文化特性初始化之 NumberFormatInfo 物件中的格式設定資訊來進行剖析。The s parameter is parsed using the formatting information in a NumberFormatInfo object that is initialized for the current system culture. 若要指定用於剖析作業之格式資訊的文化特性,請呼叫 Int32.Parse(String, NumberStyles, IFormatProvider) 多載。To specify the culture whose formatting information is used for the parse operation, call the Int32.Parse(String, NumberStyles, IFormatProvider) overload.

另請參閱

Parse(String)

將數字的字串表示轉換成它的對等 32 位元帶正負號的整數。Converts the string representation of a number to its 32-bit signed integer equivalent.

public:
 static int Parse(System::String ^ s);
public static int Parse (string s);
static member Parse : string -> int
Public Shared Function Parse (s As String) As Integer

參數

s
String

字串,包含要轉換的數字。A string containing a number to convert.

傳回

32 位元帶正負號的整數,與 s 中所包含的數字相等。A 32-bit signed integer equivalent to the number contained in s.

例外狀況

snulls is null.

s 的格式不正確。s is not in the correct format.

s 代表小於 MinValue 或大於 MaxValue 的數字。s represents a number less than MinValue or greater than MaxValue.

範例

下列範例示範如何使用 Int32.Parse(String) 方法,將字串值轉換成32位帶正負號的整數值。The following example demonstrates how to convert a string value into a 32-bit signed integer value using the Int32.Parse(String) method. 產生的整數值接著會顯示在主控台中。The resulting integer value is then displayed to the console.

using namespace System;

void main()
{
   array<String^>^ values = { "+13230", "-0", "1,390,146", "$190,235,421,127",
                              "0xFA1B", "163042", "-10", "007", "2147483647", 
                              "2147483648", "16e07", "134985.0", "-12034",
                              "-2147483648", "-2147483649" };
   for each (String^ value in values)
   {
      try {
         Int32 number = Int32::Parse(value); 
         Console::WriteLine("{0} --> {1}", value, number);
      }
      catch (FormatException^ e) {
         Console::WriteLine("{0}: Bad Format", value);
      }   
      catch (OverflowException^ e) {
         Console::WriteLine("{0}: Overflow", value);   
      }  
   }
}
// The example displays the following output:
//       +13230 --> 13230
//       -0 --> 0
//       1,390,146: Bad Format
//       $190,235,421,127: Bad Format
//       0xFA1B: Bad Format
//       163042 --> 163042
//       -10 --> -10
//       007 --> 7
//       2147483647 --> 2147483647
//       2147483648: Overflow
//       16e07: Bad Format
//       134985.0: Bad Format
//       -12034 --> -12034
//       -2147483648 --> -2147483648
//       -2147483649: Overflow      
using System;

public class Example
{
   public static void Main()
   {
      string[] values = { "+13230", "-0", "1,390,146", "$190,235,421,127",
                          "0xFA1B", "163042", "-10", "007", "2147483647", 
                          "2147483648", "16e07", "134985.0", "-12034",
                          "-2147483648", "-2147483649" };
      foreach (string value in values)
      {
         try {
            int number = Int32.Parse(value); 
            Console.WriteLine("{0} --> {1}", value, number);
         }
         catch (FormatException) {
            Console.WriteLine("{0}: Bad Format", value);
         }   
         catch (OverflowException) {
            Console.WriteLine("{0}: Overflow", value);   
         }  
      }
   }
}
// The example displays the following output:
//       +13230 --> 13230
//       -0 --> 0
//       1,390,146: Bad Format
//       $190,235,421,127: Bad Format
//       0xFA1B: Bad Format
//       163042 --> 163042
//       -10 --> -10
//       007 --> 7
//       2147483647 --> 2147483647
//       2147483648: Overflow
//       16e07: Bad Format
//       134985.0: Bad Format
//       -12034 --> -12034
//       -2147483648 --> -2147483648
//       -2147483649: Overflow      
Module Example
   Public Sub Main()
      Dim values() As String = { "+13230", "-0", "1,390,146", "$190,235,421,127",
                                 "0xFA1B", "163042", "-10", "007", "2147483647", 
                                 "2147483648", "16e07", "134985.0", "-12034",
                                 "-2147483648", "-2147483649"  }
      For Each value As String In values
         Try
            Dim number As Integer = Int32.Parse(value) 
            Console.WriteLine("{0} --> {1}", value, number)
         Catch e As FormatException
            Console.WriteLine("{0}: Bad Format", value)
         Catch e As OverflowException
            Console.WriteLine("{0}: Overflow", value)   
         End Try  
      Next
   End Sub
End Module
' The example displays the following output:
'       +13230 --> 13230
'       -0 --> 0
'       1,390,146: Bad Format
'       $190,235,421,127: Bad Format
'       0xFA1B: Bad Format
'       163042 --> 163042
'       -10 --> -10
'       007 --> 7
'       2147483647 --> 2147483647
'       2147483648: Overflow
'       16e07: Bad Format
'       134985.0: Bad Format
'       -12034 --> -12034
'       -2147483648 --> -2147483648
'       -2147483649: Overflow

備註

s 參數包含下列格式的數位:The s parameter contains a number of the form:

atl-ws-01[sign] 數位 [ws][ws][sign]digits[ws]

以方括弧([和])括住的專案是選擇性的。Items in square brackets ([ and ]) are optional. 下表說明每個元素。The following table describes each element.

項目Element 說明Description
wsws 選擇性的空白字元。Optional white space.
Signsign 選擇性的正負號。An optional sign.
digitsdigits 範圍從0到9的數位序列。A sequence of digits ranging from 0 to 9.

s 參數會使用 NumberStyles.Integer 樣式來加以解讀。The s parameter is interpreted using the NumberStyles.Integer style. 除了小數以外,只允許開頭和尾端空格加上前置正負號。In addition to decimal digits, only leading and trailing spaces together with a leading sign are allowed. 若要明確定義 s中可以存在的樣式元素,請使用 Int32.Parse(String, NumberStyles)Int32.Parse(String, NumberStyles, IFormatProvider) 方法。To explicitly define the style elements that can be present in s, use either the Int32.Parse(String, NumberStyles) or the Int32.Parse(String, NumberStyles, IFormatProvider) method.

s 參數會使用針對目前系統文化特性初始化的 NumberFormatInfo 物件中的格式資訊進行剖析。The s parameter is parsed using the formatting information in a NumberFormatInfo object initialized for the current system culture. 如需詳細資訊,請參閱CurrentInfoFor more information, see CurrentInfo. 若要使用一些其他文化特性的格式資訊來剖析字串,請使用 Int32.Parse(String, NumberStyles, IFormatProvider) 方法。To parse a string using the formatting information of some other culture, use the Int32.Parse(String, NumberStyles, IFormatProvider) method.

另請參閱

Parse(String, IFormatProvider)

將指定特定文化特性格式之數字的字串表示轉換成它的對等 32 位元帶正負號的整數。Converts the string representation of a number in a specified culture-specific format to its 32-bit signed integer equivalent.

public:
 static int Parse(System::String ^ s, IFormatProvider ^ provider);
public static int Parse (string s, IFormatProvider provider);
static member Parse : string * IFormatProvider -> int
Public Shared Function Parse (s As String, provider As IFormatProvider) As Integer

參數

s
String

字串,包含要轉換的數字。A string containing a number to convert.

provider
IFormatProvider

物件,提供關於 s 的特定文化特性格式資訊。An object that supplies culture-specific formatting information about s.

傳回

32 位元帶正負號的整數,與 s 中所指定的數字相等。A 32-bit signed integer equivalent to the number specified in s.

例外狀況

snulls is null.

s 的格式不正確。s is not of the correct format.

s 代表小於 MinValue 或大於 MaxValue 的數字。s represents a number less than MinValue or greater than MaxValue.

範例

下列範例是 Web 表單的按鈕 click 事件處理常式。The following example is the button click event handler of a Web form. 它會使用 HttpRequest.UserLanguages 屬性所傳回的陣列來判斷使用者的地區設定。It uses the array returned by the HttpRequest.UserLanguages property to determine the user's locale. 接著,它會具現化對應至該地區設定的 CultureInfo 物件。It then instantiates a CultureInfo object that corresponds to that locale. 屬於該 CultureInfo 物件的 NumberFormatInfo 物件接著會傳遞至 Parse(String, IFormatProvider) 方法,以將使用者的輸入轉換成 Int32 值。The NumberFormatInfo object that belongs to that CultureInfo object is then passed to the Parse(String, IFormatProvider) method to convert the user's input to an Int32 value.

protected void OkToInteger_Click(object sender, EventArgs e)
{
   string locale;
   int number;
   CultureInfo culture;

   // Return if string is empty
   if (String.IsNullOrEmpty(this.inputNumber.Text))
      return;

   // Get locale of web request to determine possible format of number
   if (Request.UserLanguages.Length == 0)
      return;
   locale = Request.UserLanguages[0];
   if (String.IsNullOrEmpty(locale))
      return;

  // Instantiate CultureInfo object for the user's locale
   culture = new CultureInfo(locale);

   // Convert user input from a string to a number
   try
   {
      number = Int32.Parse(this.inputNumber.Text, culture.NumberFormat);
   }
   catch (FormatException)
   {
      return;
   }
   catch (Exception)
   {
      return;
   }
   // Output number to label on web form
   this.outputNumber.Text = "Number is " + number.ToString();
}
Protected Sub OkToInteger_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles OkToInteger.Click
   Dim locale As String
   Dim culture As CultureInfo
   Dim number As Integer

   ' Return if string is empty
   If String.IsNullOrEmpty(Me.inputNumber.Text) Then Exit Sub

   ' Get locale of web request to determine possible format of number
   If Request.UserLanguages.Length = 0 Then Exit Sub
   locale = Request.UserLanguages(0)
   If String.IsNullOrEmpty(locale) Then Exit Sub

   ' Instantiate CultureInfo object for the user's locale
   culture = New CultureInfo(locale)

   ' Convert user input from a string to a number
   Try
      number = Int32.Parse(Me.inputNumber.Text, culture.NumberFormat)
   Catch ex As FormatException
      Exit Sub
   Catch ex As Exception
      Exit Sub
   End Try

   ' Output number to label on web form
   Me.outputNumber.Text = "Number is " & number.ToString()
End Sub

備註

Parse(String, IFormatProvider) 方法的這個多載通常用來將可以多種方式格式化的文字轉換成 Int32 值。This overload of the Parse(String, IFormatProvider) method is typically used to convert text that can be formatted in a variety of ways to an Int32 value. 例如,它可以用來將使用者輸入的文字轉換成 HTML 文字方塊中的數位值。For example, it can be used to convert the text entered by a user into an HTML text box to a numeric value.

s 參數包含下列格式的數位:The s parameter contains a number of the form:

atl-ws-01[sign] 數位 [ws][ws][sign]digits[ws]

以方括弧([和])括住的專案是選擇性的。Items in square brackets ([ and ]) are optional. 下表說明每個元素。The following table describes each element.

項目Element 說明Description
wsws 選擇性的空白字元。Optional white space.
簽署sign 選擇性的正負號。An optional sign.
digitsdigits 範圍從0到9的數位序列。A sequence of digits ranging from 0 to 9.

s 參數會使用 NumberStyles.Integer 樣式來加以解讀。The s parameter is interpreted using the NumberStyles.Integer style. 除了小數以外,只允許開頭和尾端空格加上前置正負號。In addition to decimal digits, only leading and trailing spaces together with a leading sign are allowed. 若要明確定義 s中可以存在的樣式元素,請使用 Int32.Parse(String, NumberStyles, IFormatProvider) 方法。To explicitly define the style elements that can be present in s, use the Int32.Parse(String, NumberStyles, IFormatProvider) method.

provider 參數是 IFormatProvider 的執行,例如 NumberFormatInfoCultureInfo 物件。The provider parameter is an IFormatProvider implementation, such as a NumberFormatInfo or CultureInfo object. provider 參數提供有關 s格式的特定文化特性資訊。The provider parameter supplies culture-specific information about the format of s. 如果 null``provider,則會使用目前文化特性的 NumberFormatInfo 物件。If provider is null, the NumberFormatInfo object for the current culture is used.

另請參閱

適用於