// 减法
public static string Subtract(string num1, string num2)
{
num1 = Science.MySciToNum(num1);
num2 = Science.MySciToNum(num2);
Int32 right1 = Int32.Parse(num1.Substring(num1.IndexOf('E') + 1));
Int32 right2 = Int32.Parse(num2.Substring(num2.IndexOf('E') + 1));
decimal left1 = Convert.ToDecimal(num1.Substring(0, num1.IndexOf('E')));
decimal left2 = Convert.ToDecimal(num2.Substring(0, num2.IndexOf('E')));
int len = right1 - right2;
if (right1 >= right2)
{
StringBuilder sb = new StringBuilder();
string str = "0." + sb.Append('0', right1 - right2) + left2.ToString().Replace(".", "");
Console.WriteLine(str);
decimal result = left1 - decimal.Parse(str);
string[] newNum = Adjust(result.ToString(), right1);
if (right1 > 0 || right2 > 0)
{
return(newNum[0] + "E+" + newNum[1]);
}
else
{
return(newNum[0] + "E+" + newNum[1]);
}
}
else
{
StringBuilder sb = new StringBuilder();
string str = "0." + sb.Append('0', right2 - right1 - 1) + left1.ToString().Replace(".", "");
Console.WriteLine(str);
decimal result = left2 - decimal.Parse(str);
string[] newNum = Adjust(result.ToString(), right2);
if (right1 > 0 || right2 > 0)
{
return(newNum[0] + "E+" + newNum[1]);
}
else
{
return(newNum[0] + "E-" + newNum[1]);
}
}
}