从文本/数字字符串创建变量只是一个数字-Razor CSHTML

Question

I have a variable var1 . In the current context, it is pulled from the database and will be one of those values:

2, 6, 7 6t, 7q, 8q,

The number will only ever be single digit.

The number will only ever be the first characters in the variable.

I would like to create a single character variable (the number) from the variable I have put in.

Here for instance my variable Fac1Raw has the value of 3c and I have tried to use this code:

var Fac1 = (int)(Fac1Raw.ToString().Substring(0, 1));

However I can't get it to work. Any ideas?

Answer 1

You can't convert String to integer type directly. For this, you have the Parse methods. If you know for sure the string won't be empty and first character is a digit, you can parse without catching errors:

var Fac1 = Int32.Parse(Fac1Raw.ToString().Substring(0, 1));

If you do want some validations to prevent your code from crashing:

string rawFac1 = Fac1Raw.ToString();
if (rawFac1.Length == 0 || !char.IsDigit(rawFac1[0]))
{
    //handle invalid value
}
else
{
    var Fac1 = Int32.Parse(rawFac1[0].ToString());
    //...rest of code
}