My name
is
Jon Skeet

I wanted to understand the purpose of this code snippet

Can someone please explain the purpose of this C# code. It's a code snippet in a Windows based application. Is it counting the number of keypress? What is the purpose of 13 here?

Any help would be much appreciated

 private void num2_KeyPress(object sender, KeyPressEventArgs e)
    {
      if ((int) e.KeyChar != 13)
        return;
      this.Calculate();
    }

That code is unfortunately written - KeyPressEventArgs.KeyChar basically returns the character pressed (so shift-a will return 'A' for example). 13 is just the Unicode character for "carriage return" which is returned when the user hits return. I would have written that method as:

// Possibly rename to CalculateIfReturnIsPressed or something similar.
private void num2_KeyPress(object sender, KeyPressEventArgs e)
{
    // Perform the calculation if the user hit return
    if (e.KeyChar == '\r')
    {
        Calculate();
    }
}

\r is the same character as (char) 13.

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