float num = 1.123F;
string result = num.ToString("0.##"); //1.12
Console.WriteLine(result);
result = num.ToString(".##"); //1.12
Console.WriteLine(result);
num = 0.123F;
result = num.ToString("0.##"); //0.12
Console.WriteLine(result);
result = num.ToString(".##"); //.12 //注意，此处没0了
Console.WriteLine(result);
num = 0F;
result = num.ToString("0.##"); //0
Console.WriteLine(result);
result = num.ToString(".##"); //空白 //注意，此处没0了
Console.WriteLine(result);
//价格格式
num = 10.25F;
result = num.ToString("C");
Console.WriteLine(result); //￥10.25
//科学计数法
num = 1110000;
result = num.ToString("E");
Console.WriteLine(result); //1.110000E+006
//四舍五入保留一位小数
num = 123.153F;
result = num.ToString("F1"); //四舍五入保留一位小数
Console.WriteLine(result); //123.2
//四舍五入保留2位小数
num = 123;
result = num.ToString("F2");
Console.WriteLine(result); //123.00
Console.ReadKey();