c#保留小數點后位數的方法

double dValue = 99.123456;
int iValue = 9999;
string strValue = "99.123456";
string result = "";

result = dValue.ToString("0.00");//99.12

result = Convert.ToDouble(iValue).ToString("0.00");//9999.00 

result = Convert.ToDouble(strValue).ToString("0.00"); //99.12

//得到小數點后2位的百分比,自動 加上%號;
result = Convert.ToDouble(dValue).ToString("P"); //9912.34%

//保留小數點后3位;  
result = Convert.ToDouble(strValue).ToString("f3"); //99.123