Int32.TryParse 方法

來源:

Int32.cs

來源:

Int32.cs

public:
 static bool TryParse(ReadOnlySpan<System::Byte> utf8Text, IFormatProvider ^ provider, [Runtime::InteropServices::Out] int % result) = IUtf8SpanParsable<int>::TryParse;

public static bool TryParse (ReadOnlySpan<byte> utf8Text, IFormatProvider? provider, out int result);

static member TryParse : ReadOnlySpan<byte> * IFormatProvider * int -> bool

Public Shared Function TryParse (utf8Text As ReadOnlySpan(Of Byte), provider As IFormatProvider, ByRef result As Integer) As Boolean

參數

傳回

true 如果 utf8Text 已成功剖析，則為 ，否則為 false 。

來源:

Int32.cs

來源:

Int32.cs

來源:

Int32.cs

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

參數

傳回

如果 s 轉換成功，則為 true，否則為 false。

來源:

Int32.cs

來源:

Int32.cs

來源:

Int32.cs

public:
 static bool TryParse(System::String ^ s, [Runtime::InteropServices::Out] int % result);

public static bool TryParse (string s, 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

參數

傳回

如果 s 轉換成功，則為 true，否則為 false。

範例

下列範例會 Int32.TryParse(String, Int32) 以數個不同的字串值呼叫 方法。

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 = int.TryParse(value, out number);
         if (success)
         {
            Console.WriteLine($"Converted '{value}' to {number}.");
         }
         else
         {
            Console.WriteLine($"Attempted conversion of '{value ?? "<null>"}' failed.");
         }
      }
   }
}
// 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.

open System

let values = 
   [ null; "160519"; "9432.0"; "16,667"
     "   -322   "; "+4302"; "(100);"; "01FA" ]
for value in values do
    match Int32.TryParse value with
    | true, number -> 
        printfn $"Converted '{value}' to {number}."
    | _ -> 
        printfn $"""Attempted conversion of '{if isNull value then "<null>" else value}' failed."""
         
// 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.

在此範例中，方法無法轉換的部分字串 TryParse(String, Int32) 如下：

• "9432.0". 轉換失敗，因為字串不能包含小數分隔符號;它必須只包含整數位數。

• "16,667". 轉換失敗，因為字串不能包含群組分隔符號;它必須只包含整數位數。

• "(100)". 轉換失敗，因為字串不能包含目前文化 NumberFormatInfo.NegativeSign 特性和 NumberFormatInfo.NumberNegativePattern 屬性所定義的負號。

• 「01FA」。 轉換失敗，因為字串不能包含十六進位數位;它必須只包含十進位數。

備註

方法 TryParse 就像 方法一樣 Parse ，但 TryParse 方法不會在轉換失敗時擲回例外狀況。 它不需要使用例外狀況處理，在無效且無法成功剖析的 事件 s 中測試 FormatException 。

參數 s 包含一些格式：

[ws][sign]digits[ws]

方括弧中的專案 ([ 和 ]) 是選擇性專案。 下表說明每個元素。

參數 s 會使用 NumberStyles.Integer 樣式來解譯。 除了十進位數之外，只允許開頭和尾端空格與前置符號。 若要明確定義樣式專案以及可以存在於 中的 s 特定文化特性格式資訊，請使用 Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) 方法。

參數 s 會使用針對目前系統文化特性初始化的 物件中的 NumberFormatInfo 格式資訊進行剖析。 如需詳細資訊，請參閱CurrentInfo。

此方法的 TryParse 這個多載會將 參數中的所有 s 數位解譯為十進位數。 若要剖析十六進位數位的字串標記法，請呼叫 Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) 多載。

另請參閱

• Parse(String)
• ToString()
• 在 .NET 中剖析數值字串
• Sample: .NET Core WinForms Formatting Utility (C#) (範例：.NET Core WinForms 格式化公用程式 (C#))
• Sample: .NET Core WinForms Formatting Utility (Visual Basic) (範例：.NET Core WinForms 格式化公用程式 (Visual Basic))

來源:

Int32.cs

來源:

Int32.cs

來源:

Int32.cs

public:
 static bool TryParse(ReadOnlySpan<char> s, IFormatProvider ^ provider, [Runtime::InteropServices::Out] int % result) = ISpanParsable<int>::TryParse;

public static bool TryParse (ReadOnlySpan<char> s, IFormatProvider? provider, out int result);

static member TryParse : ReadOnlySpan<char> * IFormatProvider * int -> bool

Public Shared Function TryParse (s As ReadOnlySpan(Of Char), provider As IFormatProvider, ByRef result As Integer) As Boolean

參數

傳回

true 如果 s 已成功剖析，則為 ，否則為 false 。

來源:

Int32.cs

來源:

Int32.cs

來源:

Int32.cs

public:
 static bool TryParse(System::String ^ s, IFormatProvider ^ provider, [Runtime::InteropServices::Out] int % result) = IParsable<int>::TryParse;

public static bool TryParse (string? s, IFormatProvider? provider, out int result);

static member TryParse : string * IFormatProvider * int -> bool

Public Shared Function TryParse (s As String, provider As IFormatProvider, ByRef result As Integer) As Boolean

參數

傳回

true 如果 s 已成功剖析，則為 ，否則為 false 。

來源:

Int32.cs

來源:

Int32.cs

public:
 static bool TryParse(ReadOnlySpan<System::Byte> utf8Text, System::Globalization::NumberStyles style, IFormatProvider ^ provider, [Runtime::InteropServices::Out] int % result) = System::Numerics::INumberBase<int>::TryParse;

public static bool TryParse (ReadOnlySpan<byte> utf8Text, System.Globalization.NumberStyles style, IFormatProvider? provider, out int result);

static member TryParse : ReadOnlySpan<byte> * System.Globalization.NumberStyles * IFormatProvider * int -> bool

Public Shared Function TryParse (utf8Text As ReadOnlySpan(Of Byte), style As NumberStyles, provider As IFormatProvider, ByRef result As Integer) As Boolean

參數

傳回

true 如果 utf8Text 已成功剖析，則為 ，否則為 false 。

來源:

Int32.cs

來源:

Int32.cs

public:
 static bool TryParse(ReadOnlySpan<System::Byte> utf8Text, [Runtime::InteropServices::Out] int % result);

public static bool TryParse (ReadOnlySpan<byte> utf8Text, out int result);

static member TryParse : ReadOnlySpan<byte> * int -> bool

Public Shared Function TryParse (utf8Text As ReadOnlySpan(Of Byte), ByRef result As Integer) As Boolean

參數

傳回

如果 utf8Text 轉換成功，則為 true，否則為 false。

來源:

Int32.cs

來源:

Int32.cs

來源:

Int32.cs

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, [Runtime::InteropServices::Out] int % result) = System::Numerics::INumberBase<int>::TryParse;

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

參數

傳回

如果 s 轉換成功，則為 true，否則為 false。

來源:

Int32.cs

來源:

Int32.cs

來源:

Int32.cs

public:
 static bool TryParse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider, [Runtime::InteropServices::Out] int % result);

public:
 static bool TryParse(System::String ^ s, System::Globalization::NumberStyles style, IFormatProvider ^ provider, [Runtime::InteropServices::Out] int % result) = System::Numerics::INumberBase<int>::TryParse;

public static bool TryParse (string s, System.Globalization.NumberStyles style, IFormatProvider provider, 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

參數

傳回

如果 s 轉換成功，則為 true，否則為 false。

例外狀況

範例

下列範例會 Int32.TryParse(String, NumberStyles, IFormatProvider, Int32) 使用數個不同的字串和 NumberStyles 值來呼叫 方法。

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 = int.TryParse(stringToConvert, styles,
                                   provider, out int number);
      if (success)
         Console.WriteLine($"Converted '{stringToConvert}' to {number}.");
      else
         Console.WriteLine($"Attempted conversion of '{stringToConvert}' failed.");
   }
}
// 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.

open System
open System.Globalization

let callTryParse (stringToConvert: string) styles =
    let provider =
        // If currency symbol is allowed, use en-US culture.
        if int (styles &&& NumberStyles.AllowCurrencySymbol) > 0 then
            CultureInfo "en-US"
        else
            CultureInfo.InvariantCulture

    match Int32.TryParse(stringToConvert, styles, provider) with
    | true, number ->
        printfn $"Converted '{stringToConvert}' to {number}."
    | _ ->
        printfn $"Attempted conversion of '{stringToConvert}' failed."

[<EntryPoint>]
let main _ =
    let numericString = "106779"
    let styles = NumberStyles.Integer
    callTryParse numericString styles

    let numericString = "-30677"
    let styles = NumberStyles.None
    callTryParse numericString styles

    let styles = NumberStyles.AllowLeadingSign
    callTryParse numericString styles

    let numericString = "301677-"
    callTryParse numericString styles

    let styles = styles ||| NumberStyles.AllowTrailingSign
    callTryParse numericString styles

    let numericString = "$10634"
    let styles = NumberStyles.Integer
    callTryParse numericString styles

    let styles = NumberStyles.Integer ||| NumberStyles.AllowCurrencySymbol
    callTryParse numericString styles

    let numericString = "10345.00"
    let styles = NumberStyles.Integer ||| NumberStyles.AllowDecimalPoint
    callTryParse numericString styles

    let numericString = "10345.72"
    let styles = NumberStyles.Integer ||| NumberStyles.AllowDecimalPoint
    callTryParse numericString styles

    let numericString = "22,593"
    let styles = NumberStyles.Integer ||| NumberStyles.AllowThousands
    callTryParse numericString styles

    let numericString = "12E-01"
    let styles = NumberStyles.Integer ||| NumberStyles.AllowExponent
    callTryParse numericString styles

    let numericString = "12E03"
    callTryParse numericString styles

    let numericString = "80c1"
    callTryParse numericString NumberStyles.HexNumber

    let numericString = "0x80C1"
    callTryParse numericString NumberStyles.HexNumber

    0

// 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.

備註

方法 TryParse 就像 方法一樣 Parse ，但 TryParse 方法不會在轉換失敗時擲回例外狀況。 它不需要使用例外狀況處理在無效且無法成功剖析的 事件 s 中測試 FormatException 。

參數 style 會定義樣式專案 (，例如空白字元或正負號) ，參數中 s 允許剖析作業成功。 它必須是列舉中的 NumberStyles 位旗標組合。 根據 的值 style ， s 參數可能包含下列元素：

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

或者，如果 style 參數包含 AllowHexSpecifier ：

[ws]hexdigits[ws]

方括弧中的專案 ([ 和 ]) 是選擇性專案。 下表說明每個元素。

只有十進位數的字串 (對應至 NumberStyles.None 旗標) 一律會成功剖析。 大部分的其餘 NumberStyles 成員控制項專案可能存在，但不需要出現在這個輸入字串中。 下表指出個別 NumberStyles 成員如何影響 中 s 可能存在的專案。

NumberStyles.AllowHexSpecifier如果使用 旗標， s 必須是不含前置詞的十六進位值。 例如，「C9AF3」 會成功剖析，但 「0xC9AF3」 則不會。 唯一可以存在的 style 旗標是 NumberStyles.AllowLeadingWhite 和 NumberStyles.AllowTrailingWhite 。 (NumberStyles 列舉具有複合樣式， NumberStyles.HexNumber 其中包含兩個空白字元旗標。)

參數 provider 是 實 IFormatProvider 作，例如 CultureInfo 物件或 NumberFormatInfo 物件，其 GetFormat 方法會 NumberFormatInfo 傳回 物件。 物件 NumberFormatInfo 提供有關 格式 s 的文化特性特定資訊。 如果 為 providernull ，則會 NumberFormatInfo 使用目前文化特性的物件。

另請參閱

• Parse(String)
• NumberStyles
• ToString()
• 在 .NET 中剖析數值字串