KeyDown event - how to easily know if the key pressed is numeric?

Question

I am currently handling the KeyDown event of a DataGridView control. One of the columns is filled by calculated values and I want the user to be able to override the cell va

Answer 1

Just get the last char from the Key that will be number if a number was pressed. This method works with KeyDown events not needing any other conditions.

Just call this static method and pass in the Key to check

public static bool IsNumber(Keys key)
{
  string num = key.ToString().Substring(key.ToString().Length - 1);
  Int64 i64;
  if (Int64.TryParse(num, out i64))
  {
    return true;               
  }
  return false;
}

Answer 2

On the msdn help page they use this code in their example:

// Determine whether the keystroke is a number from the top of the keyboard.
if (e.KeyCode < Keys.D0 || e.KeyCode > Keys.D9)

...

// Determine whether the keystroke is a number from the keypad.
if (e.KeyCode < Keys.NumPad0 || e.KeyCode > Keys.NumPad9)