C#标准数字格式字符串输出示例

出自：http://www.csharpwin.com/csharpspace/9371r9651.shtml

货币

格式字符串	区域性	数据类型	值	输出
C	en-US	Double	12345.6789	$12,345.68
C	de-DE	Double	12345.678	12.345,68 €

十进制数

格式字符串	区域性	数据类型	值	输出
D	en-US	Int32	12345	12345
D8	en-US	Int32	12345	00012345

科学记数法（指数）

格式字符串	区域性	数据类型	值	输出
E	en-US	Double	12345.6789	1.234568E+004
E10	en-US	Double	12345.6789	1.2345678900E+004
E	fr-FR	Double	12345.6789	1,234568E+004
e4	en-US	Double	12345.6789	1.2346e+004

定点

格式字符串	区域性	数据类型	值	输出
F	en-US	Double	12345.6789	12345.68
F	es-ES	Double	12345.6789	12345,68
F0	en-US	Double	12345.6789	123456
F6	en-US	Double	12345.6789	12345.678900

常规

格式字符串	区域性	数据类型	值	输出
G	en-US	Double	12345.6789	12345.6789
G7	en-US	Double	12345.6789	12345.68
G	en-US	Double	0.0000023	2.3E-6
G	en-US	Double	0.0023	0.0023
G2	en-US	Double	1234	1.2E3
G	en-US	Double	Math.PI	3.14159265358979

数字

格式字符串	区域性	数据类型	值	输出
N	en-US	Double	12345.6789	12,345.68
N	sv-SE	Double	12345.6789	12 345,68
N4	en-US	Double	123456789	123,456,789.0000

百分比

格式字符串	区域性	数据类型	值	输出
P	en-US	Double	.126	12.60 %

往返过程

格式字符串	区域性	数据类型	值	输出
r	en-US	Double	Math.PI	3.141592653589793

十六进制数

格式字符串	区域性	数据类型	值	输出
x	en-US	Int32	0x2c45e	2c45e
X	en-US	Int32	0x2c45e	2C45E
X8	en-US	Int32	0x2c45e	0002C45E
x	en-US	Int32	123456789	75bcd15

示例

下面的代码示例使用线程当前区域性、指定区域性以及所有标准数字格式对一个整型数值和一个浮点型数值进行格式化。本代码示例使用两种特定数值类型，但对于任一基本数值类型（Byte、SByte、Int16、Int32、Int64、UInt16、UInt64、Decimal、Single 和 Double）将产生类似的结果。

// This code example demonstrates the ToString(String) and 

// ToString(String, IFormatProvider) methods for integral and

// floating-point numbers, in conjunction with the standard 

// numeric format specifiers.

// This code example uses the System.Int32 integral type and 

// the System.Double floating-point type, but would yield 

// similar results for any of the numeric types. The integral 

// numeric types are System.Byte, SByte, Int16, Int32, Int64, 

// UInt16, UInt32, and UInt64. The floating-point numeric types 

// are Decimal, Single, and Double.



using System;

using System.Globalization;

using System.Threading;



class Sample 

{

    public static void Main() 

    {

// Format a negative integer or floating-point number in various ways.

    int    integralVal = -12345;

    double floatingVal = -1234.567d;



    string msgCurrency =    "(C) Currency: . . . . . . ";

    string msgDecimal  =    "(D) Decimal:. . . . . . . ";

    string msgScientific =  "(E) Scientific: . . . . . ";

    string msgFixedPoint =  "(F) Fixed point:. . . . . ";

    string msgGeneral =     "(G) General (default):. . ";

    string msgNumber =      "(N) Number: . . . . . . . ";

    string msgPercent =     "(P) Percent:. . . . . . . ";

    string msgRoundTrip =   "(R) Round-trip: . . . . . ";

    string msgHexadecimal = "(X) Hexadecimal:. . . . . ";



    string msg1 = "Use ToString(String) and the current thread culture.\n";

    string msg2 = "Use ToString(String, IFormatProvider)“ + 

        ” and a specified culture.\n";

    string msgCulture     = "Culture:";

    string msgIntegralVal = "Integral value:";

    string msgFloatingVal = "Floating-point value:";



    CultureInfo ci;

//

    Console.Clear();

    Console.WriteLine("Standard Numeric Format Specifiers:\n");

// Display the values.

    Console.WriteLine(msg1);



// Display the thread current culture, which is used to format the values.

    ci = Thread.CurrentThread.CurrentCulture;

    Console.WriteLine("{0,-26}{1}", msgCulture, ci.DisplayName);



// Display the integral and floating-point values.

    Console.WriteLine("{0,-26}{1}", msgIntegralVal, integralVal);

    Console.WriteLine("{0,-26}{1}", msgFloatingVal, floatingVal);

    Console.WriteLine();



// Use the format specifiers that are only for integral types.

    Console.WriteLine("Format specifiers only for integral types:");

    Console.WriteLine(msgDecimal     + integralVal.ToString("D"));

    Console.WriteLine(msgHexadecimal + integralVal.ToString("X"));

    Console.WriteLine();



// Use the format specifier that is only for the Single and Double 

// floating-point types.

    Console.WriteLine("Format specifier only for the Single and Double types:");

    Console.WriteLine(msgRoundTrip   + floatingVal.ToString("R"));

    Console.WriteLine();



// Use the format specifiers that are for integral or floating-point types.

    Console.WriteLine("Format specifiers for integral or floating-point types:");

    Console.WriteLine(msgCurrency    + floatingVal.ToString("C"));

    Console.WriteLine(msgScientific  + floatingVal.ToString("E"));

    Console.WriteLine(msgFixedPoint  + floatingVal.ToString("F"));

    Console.WriteLine(msgGeneral     + floatingVal.ToString("G"));

    Console.WriteLine(msgNumber      + floatingVal.ToString("N"));

    Console.WriteLine(msgPercent     + floatingVal.ToString("P"));

    Console.WriteLine();



// Display the same values using a CultureInfo object. The CultureInfo class 

// implements IFormatProvider.

    Console.WriteLine(msg2);



// Display the culture used to format the values. 

// Create a European culture and change its currency symbol to "euro" because 

// this particular code example uses a thread current UI culture that cannot 

// display the euro symbol (€).

    ci = new CultureInfo("de-DE");

    ci.NumberFormat.CurrencySymbol = "euro";

    Console.WriteLine("{0,-26}{1}", msgCulture, ci.DisplayName);



// Display the integral and floating-point values.

    Console.WriteLine("{0,-26}{1}", msgIntegralVal, integralVal);

    Console.WriteLine("{0,-26}{1}", msgFloatingVal, floatingVal);

    Console.WriteLine();



// Use the format specifiers that are only for integral types.

    Console.WriteLine("Format specifiers only for integral types:");

    Console.WriteLine(msgDecimal     + integralVal.ToString("D", ci));

    Console.WriteLine(msgHexadecimal + integralVal.ToString("X", ci));

    Console.WriteLine();



// Use the format specifier that is only for the Single and Double 

// floating-point types.

    Console.WriteLine("Format specifier only for the Single and Double types:");

    Console.WriteLine(msgRoundTrip   + floatingVal.ToString("R", ci));

    Console.WriteLine();



// Use the format specifiers that are for integral or floating-point types.

    Console.WriteLine("Format specifiers for integral or floating-point types:");

    Console.WriteLine(msgCurrency    + floatingVal.ToString("C", ci));

    Console.WriteLine(msgScientific  + floatingVal.ToString("E", ci));

    Console.WriteLine(msgFixedPoint  + floatingVal.ToString("F", ci));

    Console.WriteLine(msgGeneral     + floatingVal.ToString("G", ci));

    Console.WriteLine(msgNumber      + floatingVal.ToString("N", ci));

    Console.WriteLine(msgPercent     + floatingVal.ToString("P", ci));

    Console.WriteLine();

    }

}

/*

This code example produces the following results:



Standard Numeric Format Specifiers:



Use ToString(String) and the current thread culture.



Culture:                  English (United States)

Integral value:           -12345

Floating-point value:     -1234.567



Format specifiers only for integral types:

(D) Decimal:. . . . . . . -12345

(X) Hexadecimal:. . . . . FFFFCFC7



Format specifier only for the Single and Double types:

(R) Round-trip: . . . . . -1234.567



Format specifiers for integral or floating-point types:

(C) Currency: . . . . . . ($1,234.57)

(E) Scientific: . . . . . -1.234567E+003

(F) Fixed point:. . . . . -1234.57

(G) General (default):. . -1234.567

(N) Number: . . . . . . . -1,234.57

(P) Percent:. . . . . . . -123,456.70 %



Use ToString(String, IFormatProvider) and a specified culture.



Culture:                  German (Germany)

Integral value:           -12345

Floating-point value:     -1234.567



Format specifiers only for integral types:

(D) Decimal:. . . . . . . -12345

(X) Hexadecimal:. . . . . FFFFCFC7



Format specifier only for the Single and Double types:

(R) Round-trip: . . . . . -1234,567



Format specifiers for integral or floating-point types:

(C) Currency: . . . . . . -1.234,57 euro

(E) Scientific: . . . . . -1,234567E+003

(F) Fixed point:. . . . . -1234,57

(G) General (default):. . -1234,567

(N) Number: . . . . . . . -1.234,57

(P) Percent:. . . . . . . -123.456,70%



*/

作者：佚名