Int32.Parse Int32.Parse Int32.Parse Int32.Parse Method

定义

将数字的字符串表示形式转换为它的等效 32 位有符号整数。Converts the string representation of a number to its 32-bit signed integer equivalent.

重载

Parse(String, NumberStyles, IFormatProvider) Parse(String, NumberStyles, IFormatProvider) Parse(String, NumberStyles, IFormatProvider) Parse(String, NumberStyles, IFormatProvider)

将指定样式和区域性特定格式的数字的字符串表示形式转换为它的等效 32 位有符号整数。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) Parse(ReadOnlySpan<Char>, NumberStyles, IFormatProvider) Parse(ReadOnlySpan<Char>, NumberStyles, IFormatProvider)
Parse(String, NumberStyles) Parse(String, NumberStyles) Parse(String, NumberStyles) Parse(String, NumberStyles)

将指定样式的数字的字符串表示形式转换为它的等效 32 位有符号整数。Converts the string representation of a number in a specified style to its 32-bit signed integer equivalent.

Parse(String) Parse(String) Parse(String) Parse(String)

将数字的字符串表示形式转换为它的等效 32 位有符号整数。Converts the string representation of a number to its 32-bit signed integer equivalent.

Parse(String, IFormatProvider) Parse(String, IFormatProvider) Parse(String, IFormatProvider) Parse(String, IFormatProvider)

将指定的区域性特定格式的数字的字符串表示形式转换为它的等效 32 位有符号整数。Converts the string representation of a number in a specified culture-specific format to its 32-bit signed integer equivalent.

Parse(String, NumberStyles, IFormatProvider) Parse(String, NumberStyles, IFormatProvider) Parse(String, NumberStyles, IFormatProvider) Parse(String, NumberStyles, IFormatProvider)

将指定样式和区域性特定格式的数字的字符串表示形式转换为它的等效 32 位有符号整数。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

参数

s
String String String String

包含要转换的数字的字符串。A string containing a number to convert.

style
NumberStyles NumberStyles NumberStyles NumberStyles

枚举值的按位组合,用于指示可出现在 s 中的样式元素。A bitwise combination of enumeration values that indicates the style elements that can be present in s. 要指定的一个典型值为 IntegerA typical value to specify is Integer.

provider
IFormatProvider IFormatProvider IFormatProvider IFormatProvider

一个对象,用于提供有关 s 格式的区域性特定信息。An object that supplies culture-specific information about the format of s.

返回

s 中指定的数字等效的 32 位带符号整数。A 32-bit signed integer equivalent to the number specified in s.

异常

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

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

s 的格式不符合 styles is not in a format compliant with style.

s 表示一个小于 MinValue 或大于 MaxValue 的数字。s represents a number less than MinValue or greater than MaxValue.

- 或 --or- s 包含非零的小数位。s includes non-zero, fractional digits.

示例

下面的示例使用的各种styleprovider参数来分析的字符串表示形式Int32值。The following example uses a variety of style and provider parameters to parse the string representations of Int32 values. 它还演示了一些相同的字符串可以解释具体取决于其格式设置信息用于在分析操作的区域性的不同方法。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.

注解

style参数定义中允许的样式元素 (如空格或正号)s分析操作成功的参数。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. 它必须是从位标志的组合NumberStyles枚举。It must be a combination of bit flags from the NumberStyles enumeration. 具体取决于值style,则s参数可能包含以下元素:Depending on the value of style, the s parameter may include the following elements:

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

或者,如果style包括AllowHexSpecifier:Or, if style includes AllowHexSpecifier:

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

在方括号 ([和]) 是可选的项。Items in square brackets ([ and ]) are optional. 下表对每个元素进行了描述。The following table describes each element.

元素Element 描述Description
wsws 可选的空白区域。Optional white space. 空白可以出现在开头s如果style包括NumberStyles.AllowLeadingWhite标志,它可以出现在末尾s如果style包括NumberStyles.AllowTrailingWhite标志。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.
$ 特定于区域性的货币符号。A culture-specific currency symbol. 在字符串中的位置由NumberFormatInfo.CurrencyPositivePattern的属性NumberFormatInfo返回的对象GetFormat方法的provider参数。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. 货币符号可以出现在s如果style包括NumberStyles.AllowCurrencySymbol标志。The currency symbol can appear in s if style includes the NumberStyles.AllowCurrencySymbol flag.
signsign 一个可选符号后。An optional sign. 符号可以显示在开头s如果style包括NumberStyles.AllowLeadingSign标志或结尾处s如果style包括NumberStyles.AllowTrailingSign标志。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. 可以在使用括号s指示负值style包括NumberStyles.AllowParentheses标志。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
从 0 到 9 的数字的序列。A sequence of digits from 0 through 9. 有关fractional_digits、 仅数字 0 是有效。For fractional_digits, only the digit 0 is valid.
, 特定于区域性的千位分隔符号。A culture-specific thousands separator symbol. 千位分隔符的指定的区域性provider可以出现在s如果style包括NumberStyles.AllowThousands标志。The thousands separator of the culture specified by provider can appear in s if style includes the NumberStyles.AllowThousands flag.
.. 特定于区域性的小数点符号。A culture-specific decimal point symbol. 指定的区域性的小数点符号provider可以出现在s如果style包括NumberStyles.AllowDecimalPoint标志。The decimal point symbol of the culture specified by provider can appear in s if style includes the NumberStyles.AllowDecimalPoint flag.

数字 0 可以显示为分析操作成功; 一个小数数字如果fractional_digits包括任何其他数字OverflowException引发。Only 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 或者 E 字符,它指示指数记数法中表示值。The 'e' or 'E' character, which indicates that the value is represented in exponential notation. s参数可以表示指数表示法的数字,如果style包括NumberStyles.AllowExponent标志。The s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.
hexdigitshexdigits 一系列十六进制数字从 0 到 f 或从 0 到 f。A sequence of hexadecimal digits from 0 through f, or 0 through F.

备注

中的任何终止 NUL (U + 0000) 字符s在分析操作,而不考虑的值,将忽略style参数。Any terminating NUL (U+0000) characters in s are ignored by the parsing operation, regardless of the value of the style argument.

仅带有十进制数字的字符串 (对应于NumberStyles.None样式) 始终在成功完成分析,如果它处于范围内的Int32类型。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. 其余的大多数NumberStyles成员控件可能但不是要求必须包含在此输入字符串中的元素。Most of the remaining NumberStyles members control elements that may be but are not required to be present in this input string. 下表指示个别NumberStyles成员影响可能会出现在元素sThe following table indicates how individual NumberStyles members affect the elements that may be present in s.

非复合 NumberStyles 值Non-composite NumberStyles values 除数字之外 s 中允许的元素Elements permitted in s in addition to digits
NumberStyles.None 十进制数字。Decimal digits only.
NumberStyles.AllowDecimalPoint 小数点 ( The decimal point ( . ) 和小数位数元素。) and fractional-digits elements. 但是,小数位数必须包含一个或多个数字 0 或OverflowException引发。However, fractional-digits must consist of only one or more 0 digits or an OverflowException is thrown.
NumberStyles.AllowExponent s参数还可以使用指数记数法。The s parameter can also use exponential notation. 如果s表示一个指数表示法数字时,它必须表示一个整数的范围内Int32不带小数部分非零值的数据类型。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 Ws开头的元素sThe ws element at the beginning of s.
NumberStyles.AllowTrailingWhite Ws结尾的元素sThe ws element at the end of s.
NumberStyles.AllowLeadingSign 可以在其之前显示正号位数A positive sign can appear before digits.
NumberStyles.AllowTrailingSign 之后可以显示正号位数A positive sign can appear after digits.
NumberStyles.AllowParentheses 登录形式的括号内包含的数字值的元素。The sign element in the form of parentheses enclosing the numeric value.
NumberStyles.AllowThousands 千位分隔符 ( ) 元素。The thousands separator ( , ) element.
NumberStyles.AllowCurrencySymbol $ 元素。The $ element.

如果NumberStyles.AllowHexSpecifier使用标志,s必须是不带前缀的十六进制值。If the NumberStyles.AllowHexSpecifier flag is used, s must be a hexadecimal value without a prefix. 例如,"C9AF3"分析成功,但是"0xC9AF3"却没有。For example, "C9AF3" parses successfully, but "0xC9AF3" does not. 其他标志只有可出现在styleNumberStyles.AllowLeadingWhiteNumberStyles.AllowTrailingWhiteThe only other flags that can be present in style are NumberStyles.AllowLeadingWhite and NumberStyles.AllowTrailingWhite. (NumberStyles枚举具有复合数字样式NumberStyles.HexNumber,其中包含这两个空白标志。)(The NumberStyles enumeration has a composite number style, NumberStyles.HexNumber, that includes both white space flags.)

provider参数是IFormatProvider实现,如NumberFormatInfoCultureInfo对象。The provider parameter is an IFormatProvider implementation, such as a NumberFormatInfo or CultureInfo object. provider参数提供在分析中使用的区域性特定信息。The provider parameter supplies culture-specific information used in parsing. 如果providernull,则NumberFormatInfo对象使用当前区域性。If provider is null, the NumberFormatInfo object for the current culture is used.

另请参阅

Parse(ReadOnlySpan<Char>, NumberStyles, IFormatProvider) Parse(ReadOnlySpan<Char>, NumberStyles, IFormatProvider) Parse(ReadOnlySpan<Char>, NumberStyles, IFormatProvider)

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

参数

返回

Parse(String, NumberStyles) Parse(String, NumberStyles) Parse(String, NumberStyles) Parse(String, NumberStyles)

将指定样式的数字的字符串表示形式转换为它的等效 32 位有符号整数。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

参数

s
String String String String

包含要转换的数字的字符串。A string containing a number to convert.

style
NumberStyles NumberStyles NumberStyles NumberStyles

枚举值的按位组合,用于指示可出现在 s 中的样式元素。A bitwise combination of the enumeration values that indicates the style elements that can be present in s. 要指定的一个典型值为 IntegerA typical value to specify is Integer.

返回

s 中指定的数字等效的 32 位带符号整数。A 32-bit signed integer equivalent to the number specified in s.

异常

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

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

s 的格式不符合 styles is not in a format compliant with style.

s 表示一个小于 MinValue 或大于 MaxValue 的数字。s represents a number less than MinValue or greater than MaxValue.

- 或 --or- s 包含非零的小数位。s includes non-zero, fractional digits.

示例

下面的示例使用Int32.Parse(String, NumberStyles)方法来分析多个字符串表示形式Int32值。The following example uses the Int32.Parse(String, NumberStyles) method to parse the string representations of several Int32 values. 该示例的当前区域性为 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.

注解

style参数定义的样式元素 (如空格、 正或负号符号或千位分隔符号) 中允许s分析操作成功的参数。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. 它必须是从位标志的组合NumberStyles枚举。It must be a combination of bit flags from the NumberStyles enumeration. 具体取决于值style,则s参数可能包含以下元素: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包括AllowHexSpecifier:Or, if style includes AllowHexSpecifier:

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

在方括号 ([和]) 是可选的项。Items in square brackets ([ and ]) are optional. 下表对每个元素进行了描述。The following table describes each element.

元素Element 描述Description
wsws 可选的空白区域。Optional white space. 空白可以出现在开头s如果style包括NumberStyles.AllowLeadingWhite标志,它可以出现在末尾s如果style包括NumberStyles.AllowTrailingWhite标志。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.
$ 特定于区域性的货币符号。A culture-specific currency symbol. 在字符串中的位置由NumberFormatInfo.CurrencyNegativePatternNumberFormatInfo.CurrencyPositivePattern当前区域性的属性。Its position in the string is defined by the NumberFormatInfo.CurrencyNegativePattern and NumberFormatInfo.CurrencyPositivePattern properties of the current culture. 当前区域性的货币符号可以出现在s如果style包括NumberStyles.AllowCurrencySymbol标志。The current culture's currency symbol can appear in s if style includes the NumberStyles.AllowCurrencySymbol flag.
signsign 一个可选符号后。An optional sign. 符号可以显示在开头s如果style包括NumberStyles.AllowLeadingSign标志,它可以出现在末尾s如果style包括NumberStyles.AllowTrailingSign标志。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. 可以在使用括号s指示负值style包括NumberStyles.AllowParentheses标志。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
从 0 到 9 的数字的序列。A sequence of digits from 0 through 9. 有关fractional_digits、 仅数字 0 是有效。For fractional_digits, only the digit 0 is valid.
, 特定于区域性的千位分隔符号。A culture-specific thousands separator symbol. 当前区域性的千位分隔符可以出现在s如果style包括NumberStyles.AllowThousands标志。The current culture's thousands separator can appear in s if style includes the NumberStyles.AllowThousands flag.
.. 特定于区域性的小数点符号。A culture-specific decimal point symbol. 当前区域性的小数点符号可以出现在s如果style包括NumberStyles.AllowDecimalPoint标志。The current culture's decimal point symbol can appear in s if style includes the NumberStyles.AllowDecimalPoint flag. 数字 0 可以显示为分析操作成功; 一个小数数字如果fractional_digits包括任何其他数字OverflowException引发。Only 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 或者 E 字符,它指示指数记数法中表示值。The 'e' or 'E' character, which indicates that the value is represented in exponential notation. s参数可以表示指数表示法的数字,如果style包括NumberStyles.AllowExponent标志。The s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.
hexdigitshexdigits 一系列十六进制数字从 0 到 f 或从 0 到 f。A sequence of hexadecimal digits from 0 through f, or 0 through F.

备注

中的任何终止 NUL (U + 0000) 字符s在分析操作,而不考虑的值,将忽略style参数。Any terminating NUL (U+0000) characters in s are ignored by the parsing operation, regardless of the value of the style argument.

仅为数字的字符串 (对应于NumberStyles.None样式) 总是可以分析成功。A string with digits only (which corresponds to the NumberStyles.None style) always parses successfully. 其余的大多数NumberStyles成员控件可能但不是要求必须包含在输入字符串中的元素。Most of the remaining NumberStyles members control elements that may be but are not required to be present in the input string. 下表指示个别NumberStyles成员影响可能会出现在元素sThe following table indicates how individual NumberStyles members affect the elements that may be present in s.

NumberStyles 值NumberStyles value 除数字之外 s 中允许的元素Elements permitted in s in addition to digits
None 位数仅元素。The digits element only.
AllowDecimalPoint 小数点 ( The decimal point ( . ) 和小数位数元素。) and fractional-digits elements.
AllowExponent s参数还可以使用指数记数法。The s parameter can also use exponential notation.
AllowLeadingWhite Ws开头的元素sThe ws element at the beginning of s.
AllowTrailingWhite Ws结尾的元素sThe ws element at the end of s.
AllowLeadingSign 符号开头的元素sThe sign element at the beginning of s.
AllowTrailingSign 符号结尾的元素sThe sign element at the end of s.
AllowParentheses 登录形式的括号内包含的数字值的元素。The sign element in the form of parentheses enclosing the numeric value.
AllowThousands 千位分隔符 ( ) 元素。The thousands separator ( , ) element.
AllowCurrencySymbol $ 元素。The $ element.
Currency 全部。All. s参数不能表示十六进制数或指数表示法的数字。The s parameter cannot represent a hexadecimal number or a number in exponential notation.
Float Ws元素的开头或末尾s登录开头s,和小数点 ( The ws element at the beginning or end of s, sign at the beginning of s, and the decimal point ( . ) 符号。) symbol. s参数还可以使用指数记数法。The s parameter can also use exponential notation.
Number wssign,千位分隔符 ( ),和小数点 ( The ws, sign, thousands separator ( , ), and decimal point ( . ) 元素。) elements.
Any 所有样式,除非s不能表示十六进制数。All styles, except s cannot represent a hexadecimal number.

如果NumberStyles.AllowHexSpecifier使用标志,s必须是不带前缀的十六进制值。If the NumberStyles.AllowHexSpecifier flag is used, s must be a hexadecimal value without a prefix. 例如,"C9AF3"分析成功,但是"0xC9AF3"却没有。For example, "C9AF3" parses successfully, but "0xC9AF3" does not. 其他标志只有可以结合s它是的参数NumberStyles.AllowLeadingWhiteNumberStyles.AllowTrailingWhiteThe only other flags that can be combined with the s parameter it are NumberStyles.AllowLeadingWhite and NumberStyles.AllowTrailingWhite. (NumberStyles枚举包括复合数字样式NumberStyles.HexNumber,其中包含这两个空白标志。)(The NumberStyles enumeration includes a composite number style, NumberStyles.HexNumber, that includes both white space flags.)

s使用中的格式设置信息分析参数NumberFormatInfo对象,将初始化为当前系统区域性。The s parameter is parsed using the formatting information in a NumberFormatInfo object that is initialized for the current system culture. 若要指定其格式设置信息用于分析操作的区域性,调用Int32.Parse(String, NumberStyles, IFormatProvider)重载。To specify the culture whose formatting information is used for the parse operation, call the Int32.Parse(String, NumberStyles, IFormatProvider) overload.

另请参阅

Parse(String) Parse(String) Parse(String) Parse(String)

将数字的字符串表示形式转换为它的等效 32 位有符号整数。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

参数

s
String String String String

包含要转换的数字的字符串。A string containing a number to convert.

返回

s 中包含的数字等效的 32 位有符号整数。A 32-bit signed integer equivalent to the number contained in s.

异常

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

s 表示一个小于 MinValue 或大于 MaxValue 的数字。s represents a number less than MinValue or greater than MaxValue.

示例

下面的示例演示如何将字符串值转换为 32 位有符号的整数值,并使用Int32.Parse(String)方法。The following example demonstrates how to convert a string value into a 32-bit signed integer value using the Int32.Parse(String) method. 然后向控制台显示生成的整数值。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

注解

s参数包含多个窗体:The s parameter contains a number of the form:

[ws][sign]digits[ws][ws][sign]digits[ws]

在方括号 ([和]) 是可选的项。Items in square brackets ([ and ]) are optional. 下表对每个元素进行了描述。The following table describes each element.

元素Element 描述Description
wsws 可选的空白区域。Optional white space.
Signsign 一个可选符号后。An optional sign.
数字digits 范围从 0 到 9 的数字的序列。A sequence of digits ranging from 0 to 9.

s参数被解释使用NumberStyles.Integer样式。The s parameter is interpreted using the NumberStyles.Integer style. 除了十进制数,允许仅前导空格和尾随空格以及前导符号。In addition to decimal digits, only leading and trailing spaces together with a leading sign are allowed. 若要显式定义的样式元素可出现在s,可以使用两种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使用中的格式设置信息分析参数NumberFormatInfo对象初始化为当前系统区域性。The s parameter is parsed using the formatting information in a NumberFormatInfo object initialized for the current system culture. 有关详情,请参阅CurrentInfoFor more information, see CurrentInfo. 若要分析使用的格式信息的一些其他区域性的字符串,请使用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.

另请参阅

Parse(String, IFormatProvider) Parse(String, IFormatProvider) Parse(String, IFormatProvider) Parse(String, IFormatProvider)

将指定的区域性特定格式的数字的字符串表示形式转换为它的等效 32 位有符号整数。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

参数

s
String String String String

包含要转换的数字的字符串。A string containing a number to convert.

provider
IFormatProvider IFormatProvider IFormatProvider IFormatProvider

一个对象,提供有关 s 的区域性特定格式设置信息。An object that supplies culture-specific formatting information about s.

返回

s 中指定的数字等效的 32 位带符号整数。A 32-bit signed integer equivalent to the number specified in s.

异常

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

s 表示一个小于 MinValue 或大于 MaxValue 的数字。s represents a number less than MinValue or greater than MaxValue.

示例

下面的示例是按钮单击事件处理程序的 Web 窗体。The following example is the button click event handler of a Web form. 它使用返回的数组HttpRequest.UserLanguages属性来确定用户的区域设置。It uses the array returned by the HttpRequest.UserLanguages property to determine the user's locale. 它然后实例化CultureInfo对应于该区域设置的对象。It then instantiates a CultureInfo object that corresponds to that locale. NumberFormatInfo所属的对象的CultureInfo对象然后传递给Parse(String, IFormatProvider)方法将用户输入转换为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

注解

此重载Parse(String, IFormatProvider)方法通常用于将可以各种方式格式化文本转换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,它可以用于将输入到 HTML 文本中用户的数字值的文本转换。For example, it can be used to convert the text entered by a user into an HTML text box to a numeric value.

s参数包含多个窗体:The s parameter contains a number of the form:

[ws][sign]digits[ws][ws][sign]digits[ws]

在方括号 ([和]) 是可选的项。Items in square brackets ([ and ]) are optional. 下表对每个元素进行了描述。The following table describes each element.

元素Element 描述Description
wsws 可选的空白区域。Optional white space.
signsign 一个可选符号后。An optional sign.
digitsdigits 范围从 0 到 9 的数字的序列。A sequence of digits ranging from 0 to 9.

s参数被解释使用NumberStyles.Integer样式。The s parameter is interpreted using the NumberStyles.Integer style. 除了十进制数,允许仅前导空格和尾随空格以及前导符号。In addition to decimal digits, only leading and trailing spaces together with a leading sign are allowed. 若要显式定义的样式元素可出现在s,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参数是IFormatProvider实现,如NumberFormatInfoCultureInfo对象。The provider parameter is an IFormatProvider implementation, such as a NumberFormatInfo or CultureInfo object. provider参数提供区域性特定信息的格式的sThe provider parameter supplies culture-specific information about the format of s. 如果providernull,则NumberFormatInfo对象使用当前区域性。If provider is null, the NumberFormatInfo object for the current culture is used.

另请参阅

适用于