Decimal.ToString メソッド (IFormatProvider)

[アーティクル]
03/28/2008

指定したカルチャ固有の書式情報を使用して、対象のインスタンスの数値を等価の String 形式に変換します。

Overloads Public Overridable Function ToString( _
   ByVal provider As IFormatProvider _) As String
[C#]
public virtual string ToString(IFormatProviderprovider);
[C++]
public: virtual String* ToString(IFormatProvider* provider);
[JScript]
public function ToString(
   provider : IFormatProvider) : String;

パラメータ

provider
カルチャ固有の書式情報を提供する IFormatProvider 。

戻り値

provider で指定された、このインスタンスの値の String 形式。

解説

パラメータ provider は、 NumberFormatInfo を取得する IFormatProvider です。 NumberFormatInfo は、このインスタンスに関するカルチャ固有の書式情報を提供します。 provider が null 参照 (Visual Basic では Nothing) の場合、このインスタンスの戻り値は、現在のカルチャの NumberFormatInfo を使用して書式設定されます。

使用例

[Visual Basic, C#, C++] ToString メソッドの複数のオーバーロードを使用して Decimal の数値を String に書式化するコード例を次に示します。

 
' Example for the Decimal.ToString( ) methods.
Imports System
Imports System.Globalization
Imports Microsoft.VisualBasic

Module DecimalToStringDemo
    
    Sub Main( )

        Dim nineBillPlus As Decimal = 9876543210.9876543210D
            
        Console.WriteLine( "This example of" & vbCrLf & _
            "   Decimal.ToString( ), " & vbCrLf & _
            "   Decimal.ToString( String )," & vbCrLf & _
            "   Decimal.ToString( IFormatProvider ), and " & _ 
            vbCrLf & "   Decimal.ToString( String, IFormat" & _
            "Provider )" & vbCrLf & "generates the following " & _
            "output when run in the [{0}] culture." & vbCrLf & _
            "Decimal numbers are formatted with various " & _
            "combinations " & vbCrLf & _
            "of format strings and IFormatProvider.", _
            CultureInfo.CurrentCulture.Name )

        ' Format the number without and with format strings.
        Console.WriteLine( vbCrLf & "IFormatProvider is not " & _
            "used; the default culture is [{0}]:", _
            CultureInfo.CurrentCulture.Name )
        Console.WriteLine( "   {0,-30}{1}", _
            "No format string:", nineBillPlus.ToString( ) )
        Console.WriteLine( "   {0,-30}{1}", _
            "'N' format string:", nineBillPlus.ToString( "N" ) )
        Console.WriteLine( "   {0,-30}{1}", _
            "'N5' format string:", nineBillPlus.ToString( "N5" ) )
            
        ' Create a CultureInfo object for another culture. Use
        ' [Dutch - The Netherlands] unless the current culture
        ' is Dutch language. In that case use [English - U.S.].
        Dim cultureName As String = IIf( _
            CultureInfo.CurrentCulture.Name.Substring( 0, 2 ) = _
                "nl", "en-US", "nl-NL" )
        Dim culture As New CultureInfo( cultureName )
            
        ' Use the CultureInfo object for an IFormatProvider.
        Console.WriteLine( vbCrLf & "A CultureInfo object " & _
            "for [{0}] is used for the IFormatProvider: ", _
            cultureName )
        Console.WriteLine( "   {0,-30}{1}", "No format string:", _
            nineBillPlus.ToString( culture ) )
        Console.WriteLine( "   {0,-30}{1}", _
            "'N5' format string:", _
            nineBillPlus.ToString( "N5", culture ) )
            
        ' Get the NumberFormatInfo object from CultureInfo, and
        ' then change the digit group size to 4 and the digit
        ' separator to '_'.
        Dim numInfo As NumberFormatInfo = culture.NumberFormat
        numInfo.NumberGroupSizes = New Integer( ) { 4 }
        numInfo.NumberGroupSeparator = "_"
            
        ' Use a NumberFormatInfo object for IFormatProvider.
        Console.WriteLine( vbCrLf & _
            "A NumberFormatInfo object with digit group " & _
            "size = 4 and " & vbCrLf & "digit separator " & _
            "= '_' is used for the IFormatProvider:" )
        Console.WriteLine( "   {0,-30}{1}", _
            "'N5' format string:", _
            nineBillPlus.ToString( "N5", culture ) )
    End Sub 
End Module 

' This example of
'    Decimal.ToString( ),
'    Decimal.ToString( String ),
'    Decimal.ToString( IFormatProvider ), and
'    Decimal.ToString( String, IFormatProvider )
' generates the following output when run in the [en-US] culture.
' Decimal numbers are formatted with various combinations
' of format strings and IFormatProvider.
' 
' IFormatProvider is not used; the default culture is [en-US]:
'    No format string:             9876543210.987654321
'    'N' format string:            9,876,543,210.99
'    'N5' format string:           9,876,543,210.98765
' 
' A CultureInfo object for [nl-NL] is used for the IFormatProvider:
'    No format string:             9876543210,987654321
'    'N5' format string:           9.876.543.210,98765
' 
' A NumberFormatInfo object with digit group size = 4 and
' digit separator = '_' is used for the IFormatProvider:
'    'N5' format string:           98_7654_3210,98765

[C#] 
// Example for the Decimal.ToString( ) methods.
using System;
using System.Globalization;
using Microsoft.VisualBasic;

class DecimalToStringDemo
{
    static void Main( )
    {
        decimal nineBillPlus = 9876543210.9876543210M;
            
        Console.WriteLine( "This example of\n" +
            "   Decimal.ToString( ), \n" +
            "   Decimal.ToString( String ),\n" +
            "   Decimal.ToString( IFormatProvider ), and \n" +
            "   Decimal.ToString( String, IFormatProvider )\n" +
            "generates the following output when run in the " +
            "[{0}] culture.\nDecimal numbers are formatted " +
            "with various combinations \nof format strings " +
            "and IFormatProvider.", 
            CultureInfo.CurrentCulture.Name );

        // Format the number without and with format strings.
        Console.WriteLine( "\nIFormatProvider is not " +
            "used; the default culture is [{0}]:", 
            CultureInfo.CurrentCulture.Name );
        Console.WriteLine( "   {0,-30}{1}", "No format string:", 
            nineBillPlus.ToString( ) );
        Console.WriteLine( "   {0,-30}{1}", "'N' format string:", 
            nineBillPlus.ToString( "N" ) );
        Console.WriteLine( "   {0,-30}{1}", "'N5' format string:", 
            nineBillPlus.ToString( "N5" ) );
            
        // Create a CultureInfo object for another culture. Use
        // [Dutch - The Netherlands] unless the current culture
        // is Dutch language. In that case use [English - U.S.].
        string cultureName = 
            CultureInfo.CurrentCulture.Name.Substring( 0, 2 ) == 
            "nl" ? "en-US" : "nl-NL";
        CultureInfo culture = new CultureInfo( cultureName );
            
        // Use the CultureInfo object for an IFormatProvider.
        Console.WriteLine( "\nA CultureInfo object " +
            "for [{0}] is used for the IFormatProvider: ", 
            cultureName );
        Console.WriteLine( "   {0,-30}{1}", "No format string:", 
            nineBillPlus.ToString( culture ) );
        Console.WriteLine( "   {0,-30}{1}", "'N5' format string:", 
            nineBillPlus.ToString( "N5", culture ) );
            
        // Get the NumberFormatInfo object from CultureInfo, and
        // then change the digit group size to 4 and the digit
        // separator to '_'.
        NumberFormatInfo numInfo = culture.NumberFormat;
        numInfo.NumberGroupSizes = new int[ ] { 4 };
        numInfo.NumberGroupSeparator = "_";
            
        // Use a NumberFormatInfo object for IFormatProvider.
        Console.WriteLine( 
            "\nA NumberFormatInfo object with digit group " +
            "size = 4 and \ndigit separator " +
            "= '_' is used for the IFormatProvider:" );
        Console.WriteLine( "   {0,-30}{1}", "'N5' format string:", 
            nineBillPlus.ToString( "N5", culture ) );
    } 
} 

/*
This example of
   Decimal.ToString( ),
   Decimal.ToString( String ),
   Decimal.ToString( IFormatProvider ), and
   Decimal.ToString( String, IFormatProvider )
generates the following output when run in the [en-US] culture.
Decimal numbers are formatted with various combinations
of format strings and IFormatProvider.

IFormatProvider is not used; the default culture is [en-US]:
   No format string:             9876543210.9876543210
   'N' format string:            9,876,543,210.99
   'N5' format string:           9,876,543,210.98765

A CultureInfo object for [nl-NL] is used for the IFormatProvider:
   No format string:             9876543210,9876543210
   'N5' format string:           9.876.543.210,98765

A NumberFormatInfo object with digit group size = 4 and
digit separator = '_' is used for the IFormatProvider:
   'N5' format string:           98_7654_3210,98765
*/

[C++] 
// Sample for the Decimal::ToString( ) methods.
#using <mscorlib.dll>
using namespace System;
using namespace System::Globalization;
using namespace System::Collections;

void main( )
{
    Decimal nineBillPlus = 
        Convert::ToDecimal( S"9876543210.9876543210" );
        
    Console::WriteLine( S"This example of\n" 
        S"   Decimal::ToString( ), \n" 
        S"   Decimal::ToString( String* ),\n" 
        S"   Decimal::ToString( IFormatProvider* ), and \n" 
        S"   Decimal::ToString( String*, IFormatProvider* )\n" 
        S"generates the following output when run in the " 
        S"[{0}] culture.\nDecimal numbers are formatted " 
        S"with various combinations \nof format strings " 
        S"and IFormatProvider.", 
        CultureInfo::CurrentCulture->Name );

    // Format the number without and with format strings.
    Console::WriteLine( S"\nIFormatProvider is not " 
        S"used; the default culture is [{0}]:", 
        CultureInfo::CurrentCulture->Name );
    Console::WriteLine( S"   {0,-30}{1}", S"No format string:", 
        nineBillPlus.ToString( ) );
    Console::WriteLine( S"   {0,-30}{1}", S"'N' format string:", 
        nineBillPlus.ToString( S"N" ) );
    Console::WriteLine( S"   {0,-30}{1}", S"'N5' format string:", 
        nineBillPlus.ToString( S"N5" ) );
        
    // Create a CultureInfo object for another culture. Use
    // [Dutch - The Netherlands] unless the current culture
    // is Dutch language. In that case use [English - U.S.].
    String* cultureName = 
        CultureInfo::CurrentCulture->Name->Substring( 0, 2 ) == 
        S"nl" ? S"en-US" : S"nl-NL";
    CultureInfo* culture = new CultureInfo( cultureName );
        
    // Use the CultureInfo object for an IFormatProvider.
    Console::WriteLine( S"\nA CultureInfo object " 
        S"for [{0}] is used for the IFormatProvider: ", 
        cultureName );
    Console::WriteLine( S"   {0,-30}{1}", S"No format string:", 
        nineBillPlus.ToString( culture ) );
    Console::WriteLine( S"   {0,-30}{1}", S"'N5' format string:", 
        nineBillPlus.ToString( S"N5", culture ) );
        
    // Get the NumberFormatInfo object from CultureInfo, and
    // then change the digit group size to 4 and the digit
    // separator to '_'.
    NumberFormatInfo* numInfo = culture->NumberFormat;
    Int32 sizes __gc [] = { 4 };
    numInfo->NumberGroupSizes = sizes;
    numInfo->NumberGroupSeparator = S"_";
        
    // Use a NumberFormatInfo object for IFormatProvider.
    Console::WriteLine( 
        S"\nA NumberFormatInfo object with digit group " 
        S"size = 4 and \ndigit separator " 
        S"= '_' is used for the IFormatProvider:" );
    Console::WriteLine( S"   {0,-30}{1}", S"'N5' format string:", 
        nineBillPlus.ToString( S"N5", culture ) );
} 

/*
This example of
   Decimal::ToString( ),
   Decimal::ToString( String* ),
   Decimal::ToString( IFormatProvider* ), and
   Decimal::ToString( String*, IFormatProvider* )
generates the following output when run in the [en-US] culture.
Decimal numbers are formatted with various combinations
of format strings and IFormatProvider.

IFormatProvider is not used; the default culture is [en-US]:
   No format string:             9876543210.9876543210
   'N' format string:            9,876,543,210.99
   'N5' format string:           9,876,543,210.98765

A CultureInfo object for [nl-NL] is used for the IFormatProvider:
   No format string:             9876543210,9876543210
   'N5' format string:           9.876.543.210,98765

A NumberFormatInfo object with digit group size = 4 and
digit separator = '_' is used for the IFormatProvider:
   'N5' format string:           98_7654_3210,98765
*/

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必要条件

プラットフォーム: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 ファミリ, .NET Compact Framework - Windows CE .NET, Common Language Infrastructure (CLI) Standard

参照

次の方法で共有

Decimal.ToString メソッド (IFormatProvider)

パラメータ

戻り値

解説

使用例

必要条件

参照

その他のリソース