格式化数值：有时，我们可能需要将数值以一定的格式来呈现，就需要对数值进行格式化。我们使用格式字符串指定格式。格式字符串采用以下形式：Axx，其中 A 为格式说明符，指定格式化类型，xx 为精度说明符，控制格式化输出的有效位数或小数位数。
|
格式说明符
|
说明
|
示例
|
输出
|
|
C
|
货币
|
2.5.ToString("C")
|
￥2.50
|
|
D
|
十进制数
|
25.ToString("D5")
|
00025
|
|
E
|
科学型
|
25000.ToString("E")
|
2.500000E+005
|
|
F
|
固定点
|
25.ToString("F2")
|
25.00
|
|
G
|
常规
|
2.5.ToString("G")
|
2.5
|
|
N
|
数字
|
2500000.ToString("N")
|
2,500,000.00
|
|
X
|
十六进制
|
255.ToString("X")
|
FF
|
{
public static void Main()
{
// Display string representations of numbers for en-us culture
CultureInfo ci = new CultureInfo("en-us");
// Output floating point values
double floating = 10761.937554; Console.WriteLine("C: {0}",
floating.ToString("C", ci)); // Displays "C: $10,761.94"
Console.WriteLine("E: {0}",
floating.ToString("E03", ci)); // Displays "E: 1.076E+004"
Console.WriteLine("F: {0}",
floating.ToString("F04", ci)); // Displays "F: 10761.9376"
Console.WriteLine("G: {0}",
floating.ToString("G", ci)); // Displays "G: 10761.937554"
Console.WriteLine("N: {0}",
floating.ToString("N03", ci)); // Displays "N: 10,761.938"
Console.WriteLine("P: {0}",
(floating/10000).ToString("P02", ci)); // Displays "P: 107.62 %"
Console.WriteLine("R: {0}",
floating.ToString("R", ci)); // Displays "R: 10761.937554"
Console.WriteLine();
// Output integral values
int integral = 8395;
Console.WriteLine("C: {0}",
integral.ToString("C", ci)); // Displays "C: $8,395.00"
Console.WriteLine("D: {0}",
integral.ToString("D6", ci)); // Displays D: 008395""
Console.WriteLine("E: {0}",
integral.ToString("E03", ci)); // Displays "E: 8.395E+003"
Console.WriteLine("F: {0}",
integral.ToString("F01", ci)); // Displays "F: 8395.0"
Console.WriteLine("G: {0}",
integral.ToString("G", ci)); // Displays "G: 8395"
Console.WriteLine("N: {0}",
integral.ToString("N01", ci)); // Displays "N: 8,395.0"
Console.WriteLine("P: {0}",
(integral/10000).ToString("P02", ci)); // Displays "P: 83.95 %"
Console.WriteLine("X: 0x{0}",
integral.ToString("X", ci)); // Displays "X: 0x20CB"
Console.WriteLine();
}
}