.NET字符串格式化的几种方法及@符号的使用

1、$字符串格式化

string name = "Levi";
int age = 34;
var date = DateTime.Now;
Console.WriteLine($"He asked, \"Is your name {name}?\",{{");
Console.WriteLine($"{name} is {age} year{(age == 1 ? "" : "s")} old.");
Console.WriteLine($"Hello, {name}! Today is {date.DayOfWeek}, it's {date:HH:mm} now.");

2、String.Format()字符串格式化

string str1 =string.Format("{0:N1}",56789);               //result: 56,789.0
 string str2 =string.Format("{0:N2}",56789);               //result: 56,789.00
 string str3 =string.Format("{0:N3}",56789);               //result: 56,789.000
 string str8 =string.Format("{0:F1}",56789);               //result: 56789.0
 string str9 =string.Format("{0:F2}",56789);               //result: 56789.00
 string str11 =(56789 / 100.0).ToString("#.##");         //result: 567.89
 string str12 =(56789 / 100).ToString("#.##");            //result: 567

3、ToString()字符串格式化

int i=12345;
Console.WriteLine(i.ToString());
//结果 12345
Console.WriteLine(i.ToString("d8"));
//结果 00012345
double i=12345.6789;
Console.WriteLine(i.ToString("f2")); //结果 12345.68
Console.WriteLine(i.ToString("f6")）;
//结果 12345.678900
double i=12345.6789;
Console.WriteLine(i.ToString("n")); //结果 12,345.68
Console.WriteLine(i.ToString("n4")); //结果 12,345.6789
DateTime dt =new DateTime(2003,5,25);
Console.WriteLine(dt.ToString("yy.M.d"));
//结果 03.5.25
Console.WriteLine(dt.ToString("yyyy年M月"));
//结果 2003年5月

4、@符号的使用

当变量与关键字具有相同的名称时，可以使用@符号

public void FormatString(string @string)
{
   Console.WriteLine($"Hello with at{@string}how are you?");
   String.Format("Hello {0}", @string);
   Console.WriteLine("Hello with at{0}how are you?",@string);
}