How to restrict the user entering some invalide keys in TestBox

[engsrini]

I am developing Login Control where the user can enter username and password. in the Username and password box i should restrict the user from entering Special Chars, and other invalid keys. i know i can compare the the value in Keydown event using Keys.Keycode, but it is very ugly to put all the Spl char comparision like if(e.Keycode==Keys.Enter || etc..). Is there any function or way to Compare the key pressed is a spl. char or not. Thanks and Regards Srini

[Anh_Tuan]

Try MaskedTextBox! But filtering using KeyDown is still my preference. -K Jup

[LongRange Shooter]

Think outside the box!!!!! You have a group of keys that you want to have disallowed from entry in a textbox. So a simple solution to this would be something like this:

 List invalidKeys = new List();
         ...
 private void ThisForm\_Load()
 {
      invalidKeys.Add(Keys.Enter);
      invalidKeys.Add(Keys.Ctl);
       ...
 }

        ...
 // keypress event handler
      if ( invalidKeys.Contains(e.Keycode) )
          e.Handled = true;

-- modified at 9:49 Thursday 13th July, 2006