How to add two strings that are numbers? [duplicate]

Answer 1

You need to parse the numbers from the strings:

string number1 = "309";
string number2 = "38";

int result = int.Parse(number1) + int.Parse(number2);

Then you can set the text equal to that string representation:

string addResult = result.ToString();

Note: Int32.Parse() will throw an exception if the format isn't correct. Consider using Int32.TryParse() for a bool way to capture an impossible parsing.