Int32.TryParse 方法

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. 一个指示操作是否成功的返回值。A return value indicates whether the operation succeeded.

重载

TryParse(String, Int32)

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. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded.

TryParse(ReadOnlySpan<Char>, Int32)

将指定样式和区域性特定格式的数字的范围表示形式转换为其等效的 32 位带符号整数。Converts the span representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded.

TryParse(String, NumberStyles, IFormatProvider, Int32)

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. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded.

TryParse(ReadOnlySpan<Char>, NumberStyles, IFormatProvider, Int32)

将指定样式和区域性特定格式的数字的范围表示形式转换为其等效的 32 位带符号整数。Converts the span representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded.

TryParse(String, Int32)

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. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded.

public:
 static bool TryParse(System::String ^ s, [Runtime::InteropServices::Out] int % result);
public static bool TryParse (string s, out int result);
static member TryParse : string * int -> bool
Public Shared Function TryParse (s As String, ByRef result As Integer) As Boolean

参数

s
String

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

result
Int32

当此方法返回时,如果转换成功,则包含与 s 中所包含的数字等效的 32 位无符号整数值;如果转换失败,则包含零。When this method returns, contains the 32-bit signed integer value equivalent of the number contained in s, if the conversion succeeded, or zero if the conversion failed. 如果 s 参数为 nullEmpty、格式不正确,或者表示的数字小于 MinValue 或大于 MaxValue,则转换失败。The conversion fails if the s parameter is null or Empty, is not of the correct format, or represents a number less than MinValue or greater than MaxValue. 此参数未经初始化即进行传递;最初在 result 中提供的任何值都会被覆盖。This parameter is passed uninitialized; any value originally supplied in result will be overwritten.

返回

Boolean

如果 true 成功转换,则为 s;否则为 falsetrue if s was converted successfully; otherwise, false.

示例

下面的示例 Int32.TryParse(String, Int32) 使用多个不同的字符串值调用方法。The following example calls the Int32.TryParse(String, Int32) method with a number of different string values.

using namespace System;


   void TryToParse(String^ value)
   {
      Int32 number;
      bool result = Int32::TryParse(value, number);
      if (result) {
         Console::WriteLine("Converted '{0}' to {1}.", value, number);
      }
      else {
         if (value == nullptr) value = "";
         Console::WriteLine("Attempted conversion of '{0}' failed.", value);
      }
   }


void main()
{
      TryToParse(nullptr);
      TryToParse("160519");
      TryToParse("9432.0");
      TryToParse("16,667");
      TryToParse("   -322   ");
      TryToParse("+4302");
      TryToParse("(100);");
      TryToParse("01FA");
}
// The example displays the following output:
//      Attempted conversion of '' failed.
//      Converted '160519' to 160519.
//      Attempted conversion of '9432.0' failed.
//      Attempted conversion of '16,667' failed.
//      Converted '   -322   ' to -322.
//      Converted '+4302' to 4302.
//      Attempted conversion of '(100);' failed.
//      Attempted conversion of '01FA' failed.
using System;

public class Example
{
   public static void Main()
   {
      String[] values = { null, "160519", "9432.0", "16,667",
                          "   -322   ", "+4302", "(100);", "01FA" };
      foreach (var value in values)
      {
         int number;

         bool success = Int32.TryParse(value, out number);
         if (success)
         {
            Console.WriteLine("Converted '{0}' to {1}.", value, number);
         }
         else
         {
            Console.WriteLine("Attempted conversion of '{0}' failed.",
                               value ?? "<null>");
         }
      }
   }
}
// The example displays the following output:
//       Attempted conversion of '<null>' failed.
//       Converted '160519' to 160519.
//       Attempted conversion of '9432.0' failed.
//       Attempted conversion of '16,667' failed.
//       Converted '   -322   ' to -322.
//       Converted '+4302' to 4302.
//       Attempted conversion of '(100);' failed.
//       Attempted conversion of '01FA' failed.
Module Example
   Public Sub Main()
      Dim values() As String = { Nothing, "160519", "9432.0", "16,667",
                                 "   -322   ", "+4302", "(100);", 
                                 "01FA" }

      For Each value In values
         Dim number As Integer
    
         Dim success As Boolean = Int32.TryParse(value, number)
         If success Then
            Console.WriteLine("Converted '{0}' to {1}.", value, number)
         Else
            Console.WriteLine("Attempted conversion of '{0}' failed.", 
                              If(value ,"<null>"))
         End If     
      Next
   End Sub
End Module
' The example displays the following output to the console:
'       Attempted conversion of '<null>' failed.
'       Converted '160519' to 160519.
'       Attempted conversion of '9432.0' failed.
'       Attempted conversion of '16,667' failed.
'       Converted '   -322   ' to -322.
'       Converted '+4302' to 4302.
'       Attempted conversion of '(100)' failed.
'       Attempted conversion of '01FA' failed.

TryParse(String, Int32)在此示例中,此方法无法转换的某些字符串是:Some of the strings that the TryParse(String, Int32) method is unable to convert in this example are:

  • "9432.0"."9432.0". 转换失败,因为字符串不能包含小数分隔符;它必须仅包含整数位数。The conversion fails because the string cannot contain a decimal separator; it must contain integral digits only.

  • "16,667"."16,667". 转换失败,因为字符串不能包含组分隔符;它必须仅包含整数位数。The conversion fails because the string cannot contain group separators; it must contain integral digits only.

  • "(100)"."(100)". 转换失败,因为该字符串不能包含由当前区域性的和属性定义的负号 NumberFormatInfo.NegativeSign NumberFormatInfo.NumberNegativePatternThe conversion fails because the string cannot contain a negative sign other than the one defined by the current culture's NumberFormatInfo.NegativeSign and NumberFormatInfo.NumberNegativePattern properties.

  • "01FA"."01FA". 转换失败,因为字符串不能包含十六进制数字;它只能包含十进制数字。The conversion fails because the string cannot contain hexadecimal digits; it must contain decimal digits only.

注解

TryParse方法与 Parse 方法类似,不同的是, TryParse 如果转换失败,方法不会引发异常。The TryParse method is like the Parse method, except the TryParse method does not throw an exception if the conversion fails. 这样,便无需使用异常处理来测试无效的 FormatException 事件, s 也不能成功分析。It eliminates the need to use exception handling to test for a FormatException in the event that s is invalid and cannot be successfully parsed.

s参数包含以下格式的编号:The s parameter contains a number of the form:

ws[sign] 位数 [ws][ws][sign]digits[ws]

方括号 ( [和] ) 中的项是可选的。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 说明Description
wsws 可选空白。Optional white space.
signsign 一个可选的符号。An optional sign.
位数digits 介于0到9之间的一系列数字。A sequence of digits ranging from 0 to 9.

s使用样式对参数进行解释 NumberStyles.IntegerThe s parameter is interpreted using the NumberStyles.Integer style. 除十进制数字外,只允许使用前导和尾随空格以及前导符号。In addition to the decimal digits, only leading and trailing spaces together with a leading sign are allowed. 若要使用中提供的区域性特定格式设置信息显式定义样式元素 s ,请使用 Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) 方法。To explicitly define the style elements together with the culture-specific formatting information that can be present in s, use the Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) method.

s使用 NumberFormatInfo 为当前系统区域性初始化的对象中的格式设置信息分析参数。The s parameter is parsed using the formatting information in a NumberFormatInfo object initialized for the current system culture. 有关详细信息,请参阅 CurrentInfoFor more information, see CurrentInfo.

此方法的重载将 TryParse 参数中的所有数字解释 s 为十进制数字。This overload of the TryParse method interprets all digits in the s parameter as decimal digits. 若要分析十六进制数的字符串表示形式,请调用 Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) 重载。To parse the string representation of a hexadecimal number, call the Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) overload.

另请参阅

适用于

TryParse(ReadOnlySpan<Char>, Int32)

将指定样式和区域性特定格式的数字的范围表示形式转换为其等效的 32 位带符号整数。Converts the span representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded.

public:
 static bool TryParse(ReadOnlySpan<char> s, [Runtime::InteropServices::Out] int % result);
public static bool TryParse (ReadOnlySpan<char> s, out int result);
static member TryParse : ReadOnlySpan<char> * int -> bool
Public Shared Function TryParse (s As ReadOnlySpan(Of Char), ByRef result As Integer) As Boolean

参数

s
ReadOnlySpan<Char>

一个范围,包含表示要转换的数字的字符。A span containing the characters that represent the number to convert.

result
Int32

当此方法返回时,如果转换成功,则包含与 s 中所包含的数字等效的 32 位无符号整数值;如果转换失败,则包含零。When this method returns, contains the 32-bit signed integer value equivalent of the number contained in s, if the conversion succeeded, or zero if the conversion failed. 如果 s 参数为 nullEmpty、格式不符合 style,或者表示的数字小于 MinValue 或大于 MaxValue,则转换失败。The conversion fails if the s parameter is null or Empty, is not in a format compliant with style, or represents a number less than MinValue or greater than MaxValue. 此参数未经初始化即进行传递;最初在 result 中提供的任何值都会被覆盖。This parameter is passed uninitialized; any value originally supplied in result will be overwritten.

返回

Boolean

如果 true 成功转换,则为 s;否则为 falsetrue if s was converted successfully; otherwise, false.

适用于

TryParse(String, NumberStyles, IFormatProvider, Int32)

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. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded.

public:
 static bool TryParse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider, [Runtime::InteropServices::Out] int % result);
public static bool TryParse (string s, System.Globalization.NumberStyles style, IFormatProvider provider, out int result);
static member TryParse : string * System.Globalization.NumberStyles * IFormatProvider * int -> bool
Public Shared Function TryParse (s As String, style As NumberStyles, provider As IFormatProvider, ByRef result As Integer) As Boolean

参数

s
String

包含要转换的数字的字符串。A string containing a number to convert. 该字符串使用由 style 指定的样式来进行解释。The string is interpreted using the style specified by style.

style
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

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.

result
Int32

当此方法返回时,如果转换成功,则包含与 s 中所包含的数字等效的 32 位无符号整数值;如果转换失败,则包含零。When this method returns, contains the 32-bit signed integer value equivalent of the number contained in s, if the conversion succeeded, or zero if the conversion failed. 如果 s 参数为 nullEmpty、格式不符合 style,或者表示的数字小于 MinValue 或大于 MaxValue,则转换失败。The conversion fails if the s parameter is null or Empty, is not in a format compliant with style, or represents a number less than MinValue or greater than MaxValue. 此参数未经初始化即进行传递;最初在 result 中提供的任何值都会被覆盖。This parameter is passed uninitialized; any value originally supplied in result will be overwritten.

返回

Boolean

如果 true 成功转换,则为 s;否则为 falsetrue if s was converted successfully; otherwise, false.

例外

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.

示例

下面的示例 Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) 使用多个不同的字符串和值调用方法 NumberStylesThe following example calls the Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) method with a number of different string and NumberStyles values.

using namespace System;
using namespace System::Globalization;

void CallTryParse(String^ stringToConvert, NumberStyles styles)
{
      Int32 number;
      CultureInfo^ provider;

      // If currency symbol is allowed, use en-US culture. 
      if (((Int32) (styles & NumberStyles::AllowCurrencySymbol)) > 0)
         provider = gcnew CultureInfo("en-US");
      else
         provider = CultureInfo::InvariantCulture;

      bool result = Int32::TryParse(stringToConvert, styles, 
                                   provider, number);
      if (result)
         Console::WriteLine("Converted '{0}' to {1}.", stringToConvert, number);
      else
         Console::WriteLine("Attempted conversion of '{0}' failed.", 
                           Convert::ToString(stringToConvert));
}

void main()
{
      String^ numericString;
      NumberStyles styles;

      numericString = "106779";
      styles = NumberStyles::Integer;
      CallTryParse(numericString, styles);

      numericString = "-30677";
      styles = NumberStyles::None;
      CallTryParse(numericString, styles);

      styles = NumberStyles::AllowLeadingSign;
      CallTryParse(numericString, styles);

      numericString = "301677-";
      CallTryParse(numericString, styles);

      styles = styles | NumberStyles::AllowTrailingSign;
      CallTryParse(numericString, styles);

      numericString = "$10634";
      styles = NumberStyles::Integer;
      CallTryParse(numericString, styles);

      styles = NumberStyles::Integer | NumberStyles::AllowCurrencySymbol;
      CallTryParse(numericString, styles);

      numericString = "10345.00";
      styles = NumberStyles::Integer | NumberStyles::AllowDecimalPoint;
      CallTryParse(numericString, styles);

      numericString = "10345.72";
      styles = NumberStyles::Integer | NumberStyles::AllowDecimalPoint;
      CallTryParse(numericString, styles);

      numericString = "22,593"; 
      styles = NumberStyles::Integer | NumberStyles::AllowThousands;
      CallTryParse(numericString, styles);

      numericString = "12E-01";
      styles = NumberStyles::Integer | NumberStyles::AllowExponent;
      CallTryParse(numericString, styles); 

      numericString = "12E03";
      CallTryParse(numericString, styles); 

      numericString = "80c1";
      CallTryParse(numericString, NumberStyles::HexNumber);

      numericString = "0x80C1";
      CallTryParse(numericString, NumberStyles::HexNumber);      
      Console::ReadLine();
}
// The example displays the following output:
//      Converted '106779' to 106779.
//      Attempted conversion of '-30677' failed.
//      Converted '-30677' to -30677.
//      Attempted conversion of '301677-' failed.
//      Converted '301677-' to -301677.
//      Attempted conversion of '$10634' failed.
//      Converted '$10634' to 10634.
//      Converted '10345.00' to 10345.
//      Attempted conversion of '10345.72' failed.
//      Converted '22,593' to 22593.
//      Attempted conversion of '12E-01' failed.
//      Converted '12E03' to 12000.
//      Converted '80c1' to 32961.
//      Attempted conversion of '0x80C1' failed.
using System;
using System.Globalization;

public class StringParsing
{
   public static void Main()
   {
      string numericString;
      NumberStyles styles;

      numericString = "106779";
      styles = NumberStyles.Integer;
      CallTryParse(numericString, styles);

      numericString = "-30677";
      styles = NumberStyles.None;
      CallTryParse(numericString, styles);

      styles = NumberStyles.AllowLeadingSign;
      CallTryParse(numericString, styles);

      numericString = "301677-";
      CallTryParse(numericString, styles);

      styles = styles | NumberStyles.AllowTrailingSign;
      CallTryParse(numericString, styles);

      numericString = "$10634";
      styles = NumberStyles.Integer;
      CallTryParse(numericString, styles);

      styles = NumberStyles.Integer | NumberStyles.AllowCurrencySymbol;
      CallTryParse(numericString, styles);

      numericString = "10345.00";
      styles = NumberStyles.Integer | NumberStyles.AllowDecimalPoint;
      CallTryParse(numericString, styles);

      numericString = "10345.72";
      styles = NumberStyles.Integer | NumberStyles.AllowDecimalPoint;
      CallTryParse(numericString, styles);

      numericString = "22,593";
      styles = NumberStyles.Integer | NumberStyles.AllowThousands;
      CallTryParse(numericString, styles);

      numericString = "12E-01";
      styles = NumberStyles.Integer | NumberStyles.AllowExponent;
      CallTryParse(numericString, styles);

      numericString = "12E03";
      CallTryParse(numericString, styles);

      numericString = "80c1";
      CallTryParse(numericString, NumberStyles.HexNumber);

      numericString = "0x80C1";
      CallTryParse(numericString, NumberStyles.HexNumber);
   }

   private static void CallTryParse(string stringToConvert, NumberStyles styles)
   {
      CultureInfo provider;

      // If currency symbol is allowed, use en-US culture.
      if ((styles & NumberStyles.AllowCurrencySymbol) > 0)
         provider = new CultureInfo("en-US");
      else
         provider = CultureInfo.InvariantCulture;

      bool success = Int32.TryParse(stringToConvert, styles,
                                   provider, out int number);
      if (success)
         Console.WriteLine("Converted '{0}' to {1}.", stringToConvert, number);
      else
         Console.WriteLine("Attempted conversion of '{0}' failed.",
                           Convert.ToString(stringToConvert));
   }
}
// The example displays the following output to the console:
//       Converted '106779' to 106779.
//       Attempted conversion of '-30677' failed.
//       Converted '-30677' to -30677.
//       Attempted conversion of '301677-' failed.
//       Converted '301677-' to -301677.
//       Attempted conversion of '$10634' failed.
//       Converted '$10634' to 10634.
//       Converted '10345.00' to 10345.
//       Attempted conversion of '10345.72' failed.
//       Converted '22,593' to 22593.
//       Attempted conversion of '12E-01' failed.
//       Converted '12E03' to 12000.
//       Converted '80c1' to 32961.
//       Attempted conversion of '0x80C1' failed.
Imports System.Globalization

Module StringParsing
   Public Sub Main()
      Dim numericString As String
      Dim styles As NumberStyles
      
      numericString = "106779"
      styles = NumberStyles.Integer
      CallTryParse(numericString, styles)
      
      numericString = "-30677"
      styles = NumberStyles.None
      CallTryParse(numericString, styles)
      
      styles = NumberStyles.AllowLeadingSign
      CallTryParse(numericString, styles)
      
      numericString = "301677-"
      CallTryParse(numericString, styles)
      
      styles = styles Or NumberStyles.AllowTrailingSign
      CallTryParse(numericString, styles)
      
      numericString = "$10634"
      styles = NumberStyles.Integer
      CallTryParse(numericString, styles)
      
      styles = NumberStyles.Integer Or NumberStyles.AllowCurrencySymbol
      CallTryParse(numericString, styles)

      numericString = "10345.00"
      styles = NumberStyles.Integer Or NumberStyles.AllowDecimalPoint
      CallTryParse(numericString, styles)
      
      numericString = "10345.72"
      styles = NumberStyles.Integer Or NumberStyles.AllowDecimalPoint
      CallTryParse(numericString, styles)

      numericString = "22,593" 
      styles = NumberStyles.Integer Or NumberStyles.AllowThousands
      CallTryParse(numericString, styles)
      
      numericString = "12E-01"
      styles = NumberStyles.Integer Or NumberStyles.AllowExponent
      CallTryParse(numericString, styles) 
          
      numericString = "12E03"
      CallTryParse(numericString, styles) 
      
      numericString = "80c1"
      CallTryParse(numericString, NumberStyles.HexNumber)
      
      numericString = "0x80C1"
      CallTryParse(numericString, NumberStyles.HexNumber)
   End Sub
   
   Private Sub CallTryParse(stringToConvert As String, styles AS NumberStyles)
      Dim number As Integer
      Dim provider As CultureInfo
      
      ' If currency symbol is allowed, use en-US culture.
      If CBool(styles And NumberStyles.AllowCurrencySymbol) Then
         provider = CultureInfo.CurrentCulture
      Else
         provider = New CultureInfo("en-US")
      End If
      
      Dim result As Boolean = Int32.TryParse(stringToConvert, styles, _
                                             provider, number)
      If result Then
         Console.WriteLine("Converted '{0}' to {1}.", stringToConvert, number)
      Else
         Console.WriteLine("Attempted conversion of '{0}' failed.", _
                           Convert.ToString(stringToConvert))
      End If                                                                           
   End Sub
End Module
' The example displays the following output to the console:
'       Converted '106779' to 106779.
'       Attempted conversion of '-30677' failed.
'       Converted '-30677' to -30677.
'       Attempted conversion of '301677-' failed.
'       Converted '301677-' to -301677.
'       Attempted conversion of '$10634' failed.
'       Converted '$10634' to 10634.
'       Converted '10345.00' to 10345.
'       Attempted conversion of '10345.72' failed.
'       Converted '22,593' to 22593.
'       Attempted conversion of '12E-01' failed.
'       Converted '12E03' to 12000.
'       Converted '80c1' to 32961.
'       Attempted conversion of '0x80C1' failed.

注解

TryParse方法与 Parse 方法类似,不同的是, TryParse 如果转换失败,方法不会引发异常。The TryParse method is like the Parse method, except the TryParse method does not throw an exception if the conversion fails. 这样,便无需使用异常处理来测试无效的 FormatException 事件, s 也不能成功分析。It eliminates the need to use exception handling to test for a FormatException in the event that s is invalid and cannot be parsed successfully.

style参数定义 ((如空白)或正号或负号) 等样式元素,以便 s 分析操作成功。The style parameter defines the style elements (such as white space or a positive or negative sign) that are allowed in the s parameter for the parse operation to succeed. 它必须是枚举中的位标志的组合 NumberStylesIt must be a combination of bit flags from the NumberStyles enumeration. 根据的值 styles 参数可能包括以下元素:Depending on the value of style, the s parameter may include the following elements:

ws[$]表明[数字,] 位数 [.fractional_digits] [e [sign] 数字] [ws][ws][$][sign][digits,]digits[.fractional_digits][e[sign]digits][ws]

或者,如果 style 参数包括 AllowHexSpecifierOr, if the style parameter includes AllowHexSpecifier:

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

方括号 ( [和] ) 中的项是可选的。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 说明Description
wsws 可选空白。Optional white space. 如果包含标志,则空白可以出现在开头; s style NumberStyles.AllowLeadingWhite s 如果 style 包含 NumberStyles.AllowTrailingWhite 标志,则为末尾处。White space can appear at the beginning of s if style includes the NumberStyles.AllowLeadingWhite flag, or at the end of s if style includes the NumberStyles.AllowTrailingWhite flag.
$ 区域性特定的货币符号。A culture-specific currency symbol. 其在字符串中的位置由 CurrencyPositivePattern NumberFormatInfo 参数方法返回的对象的属性定义 GetFormat providerIts position in the string is defined by the CurrencyPositivePattern property of the NumberFormatInfo object returned by the GetFormat method of the provider parameter. s如果包含标志,则货币符号可以出现在中 style NumberStyles.AllowCurrencySymbolThe currency symbol can appear in s if style includes the NumberStyles.AllowCurrencySymbol flag.
signsign 一个可选的符号。An optional sign. s如果 style 包含 NumberStyles.AllowLeadingSign 或标志,则符号符号可以出现在中 NumberStyles.AllowTrailingSignA sign symbol can appear in s if style includes the NumberStyles.AllowLeadingSign or NumberStyles.AllowTrailingSign flags.
位数digits 介于0到9之间的一系列数字。A sequence of digits from 0 through 9.
,, 区域性特定的千位分隔符。A culture-specific thousands separator. 如果包含标志,则指定的区域性的千位分隔符 provider 可以出现在中 s style NumberStyles.AllowThousandsThe thousands separator of the culture specified by provider can appear in s if style includes the NumberStyles.AllowThousands flag.
.. 区域性特定的小数点符号。A culture-specific decimal point symbol. 如果包含标志,则指定的区域性的小数点符号 provider 可以出现在中 s style NumberStyles.AllowDecimalPointThe decimal point symbol of the culture specified by provider can appear in s if style includes the NumberStyles.AllowDecimalPoint flag.
fractional_digitsfractional_digits 数字0的一个或多个匹配项。One or more occurrences of the digit 0. s仅当包含标志时,小数位才能出现在中 style NumberStyles.AllowDecimalPointFractional digits can appear in s only if style includes the NumberStyles.AllowDecimalPoint flag.
ee "E" 或 "E" 字符,指示值以指数表示法表示。The 'e' or 'E' character, which indicates that the value is represented in exponential notation. s如果包含标志,则参数可以表示指数表示法中的数字 style NumberStyles.AllowExponentThe s parameter can represent a number in exponential notation if style includes the NumberStyles.AllowExponent flag.
hexdigitshexdigits 从0到 f 的十六进制数字序列,或者从0到 F。A sequence of hexadecimal digits from 0 through f, or 0 through F.

备注

s无论参数的值如何,分析操作都将忽略中任何终止的 NUL (U + 0000) 字符 styleAny terminating NUL (U+0000) characters in s are ignored by the parsing operation, regardless of the value of the style argument.

只包含十进制数字的字符串 (对应于 NumberStyles.None 标记) 总是成功分析。A string with decimal digits only (which corresponds to the NumberStyles.None flag) always parses successfully. 大多数其余 NumberStyles 成员控件元素在此输入字符串中可能已存在但不是必需的。Most of the remaining NumberStyles members control elements that may be but are not required to be present in this input string. 下表指示各个成员如何 NumberStyles 影响可能出现在中的元素 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 除数字外允许在 s 中使用的元素Elements permitted in s in addition to digits
NumberStyles.None 仅十进制数字。Decimal digits only.
NumberStyles.AllowDecimalPoint 小数点 () 和 fractional_digits 元素。The decimal point ( . ) and fractional_digits elements. fractional_digits 只能包含一个或零个数字或该方法返回 falseHowever, fractional_digits must consist of only one or more 0 digits or the method returns false.
NumberStyles.AllowExponent s参数还可以使用指数表示法。The s parameter can also use exponential notation. 如果 s 表示指数表示法中的数字,则该数字必须表示数据类型范围内的一个整数,该数据类型的范围内 Int32 没有非零的小数部分。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 开头的 ws 元素 sThe ws element at the beginning of s.
NumberStyles.AllowTrailingWhite 末尾处的 ws 元素 sThe ws element at the end of s.
NumberStyles.AllowLeadingSign 符号可以出现在 数字 之前。A sign can appear before digits.
NumberStyles.AllowTrailingSign 符号可以出现在 数字 之后。A sign can appear after digits.
NumberStyles.AllowParentheses 用括号括起数值的 符号 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.
NumberStyles.Currency 所有元素。All elements. s参数不能表示十六进制数或以指数表示法表示的数字。The s parameter cannot represent a hexadecimal number or a number in exponential notation.
NumberStyles.Float 在开头或结尾处的 ws 元素,在 s 的开头处 符号s 小数点 () 符号。 .The ws element at the beginning or end of s, sign at the beginning of s, and the decimal point ( . ) symbol. s参数还可以使用指数表示法。The s parameter can also use exponential notation.
NumberStyles.Number Wssign 、千位分隔符 ( ) 和 小数点 () 元素。The ws , sign , thousands separator ( , ), and decimal point ( . ) elements.
NumberStyles.Any 除之外的所有样式都 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,则 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 "0xC9AF3" 不能。For example, "C9AF3" parses successfully, but "0xC9AF3" does not. 中可以存在的唯一其他标志 styleNumberStyles.AllowLeadingWhiteNumberStyles.AllowTrailingWhiteThe only other flags that can be present in style are NumberStyles.AllowLeadingWhite and NumberStyles.AllowTrailingWhite. (NumberStyles 枚举具有复合样式, NumberStyles.HexNumber 其中包含两个空格标志。 ) (The NumberStyles enumeration has a composite style, NumberStyles.HexNumber, that includes both white space flags.)

provider参数是一个 IFormatProvider 实现,例如 CultureInfo 对象或 NumberFormatInfo 对象,其 GetFormat 方法返回 NumberFormatInfo 对象。The provider parameter is an IFormatProvider implementation, such as a CultureInfo object or a NumberFormatInfo object, whose GetFormat method returns a NumberFormatInfo object. NumberFormatInfo对象提供有关的格式的区域性特定信息 sThe NumberFormatInfo object provides culture-specific information about the format of s. 如果 providernull ,则 NumberFormatInfo 使用当前区域性的对象。If provider is null, the NumberFormatInfo object for the current culture is used.

另请参阅

适用于

TryParse(ReadOnlySpan<Char>, NumberStyles, IFormatProvider, Int32)

将指定样式和区域性特定格式的数字的范围表示形式转换为其等效的 32 位带符号整数。Converts the span representation of a number in a specified style and culture-specific format to its 32-bit signed integer equivalent. 一个指示转换是否成功的返回值。A return value indicates whether the conversion succeeded.

public:
 static bool TryParse(ReadOnlySpan<char> s, System::Globalization::NumberStyles style, IFormatProvider ^ provider, [Runtime::InteropServices::Out] int % result);
public static bool TryParse (ReadOnlySpan<char> s, System.Globalization.NumberStyles style, IFormatProvider? provider, out int result);
public static bool TryParse (ReadOnlySpan<char> s, System.Globalization.NumberStyles style, IFormatProvider provider, out int result);
static member TryParse : ReadOnlySpan<char> * System.Globalization.NumberStyles * IFormatProvider * int -> bool
Public Shared Function TryParse (s As ReadOnlySpan(Of Char), style As NumberStyles, provider As IFormatProvider, ByRef result As Integer) As Boolean

参数

s
ReadOnlySpan<Char>

一个范围,包含表示要转换的数字的字符。A span containing the characters that represent the number to convert. 该范围使用由 style 指定的样式来进行解释The span is interpreted using the style specified by style

style
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

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.

result
Int32

当此方法返回时,如果转换成功,则包含与 s 中所包含的数字等效的 32 位无符号整数值;如果转换失败,则包含零。When this method returns, contains the 32-bit signed integer value equivalent of the number contained in s, if the conversion succeeded, or zero if the conversion failed. 如果 s 参数为 nullEmpty、格式不符合 style,或者表示的数字小于 MinValue 或大于 MaxValue,则转换失败。The conversion fails if the s parameter is null or Empty, is not in a format compliant with style, or represents a number less than MinValue or greater than MaxValue. 此参数未经初始化即进行传递;最初在 result 中提供的任何值都会被覆盖。This parameter is passed uninitialized; any value originally supplied in result will be overwritten.

返回

Boolean

如果 true 成功转换,则为 s;否则为 falsetrue if s was converted successfully; otherwise, false.

适用于