Question

I have a problem when summing all of bx3.text to t2.text.
first I split bx3.text with space

    private void total()
    {
        string[] ps = bx3.Text.Split(new string[] {" "}, StringSplitOptions.None );
        t2.Text = ps.Select(x => Convert.ToInt32(x)).Sum().ToString();
    }

I did try with t2.text = ps[1] and the number showed was correct.
but when i try to sum it all, I got error

“Input string was not in a correct format” on (x =>
Convert.ToInt32(x))

bx3.text is full of user-input number separated by single space ” “

Answer 1

Try this:

 string output = ps.Select(x =>
                                { 
                                    int myInt = 0;
                                    int.TryParse(x, out myInt);
                                    return myInt;
                                })
                                .Sum().ToString();

Above code will sum all integers in ps array and it will omit all non integer values.

First scenario: if x is integer (x=1)

  int myInt = 0;
  int.TryParse(x, out myInt); // change value of myInt to 1, because x is integer
  return myInt; // return 1

Second scenario: if x is not integer (x=”aaa”)

  int myInt = 0;
  int.TryParse(x, out myInt); // don't change value of myInt, because x is not integer
  return myInt; // return 0

If x is not integer function TryParse always set value of myInt to zero (msdn doc).