Easy way to avoid string addition in C#

June 29, 2022

I have couple of string variables that sometimes have text and other times have integers in them. I have a function Add() where I add all the variables when they are integers. Problem is how do I avoid any variable when they are string? Example:

string a = "2";
string b = "3";
string c = "10";
string d = "jk";
string e = "zu";
string f = "15";

public void Add(){
  int total = int.Parse(a) + int.Parse(b) + int.Parse(c) + int.Parse(d) + int.Parse(e) + int.Parse(f);
}

Obviously the above code will fail because d and e are string, what I am looking for is it should avoid adding d and e strings and the total should be 30. I can check if the string is an integer or a text but that would take forever if the script I am working on does not have strings as an array.
What is the right and easy way to do this?

>Solution :

If you want to use spesific variables, you can code this use case like this

void Add()
{
  int aInt, bInt, cInt, dInt, eInt, fInt;
  int.TryParse(a, out aInt);
  int.TryParse(b, out bInt);
  int.TryParse(c, out cInt);
  int.TryParse(d, out dInt);
  int.TryParse(e, out eInt);
  int.TryParse(f, out fInt);
  int total = aInt + bInt + cInt + dInt + eInt + fInt;
}

If you want to use more extendible code, you should use collection

void Add()
{
  int total = 0;
  foreach (var c in myStrCollection)
  {
    int.TryParse(c, out int a);
    total += a;
  }
}

int.TryParse will try to convert the string to int. If it cannot convert, variable a will be 0 as default. 0 is ineffective element for addition. If this method is multiplication, you should change the method like this.

void Multiply()
{
  int total = 0;
  foreach (var c in myStrCollection)
  {
    bool s = int.TryParse(c, out int a);
    if(!s) a = 1;
    total *= a;
  }
}