This is a function normally found in the C language. However it is useful to script developers as well and may be available in some implementations as an extension to the ECMA standard functionality.

This function tests to see if a character is a control code. It will return true for any character in the following set:

Strictly speaking, this function should be coded to be aware of locale specific issues. You may want to take the example simulation provided here and modify it to your own needs to support that. This is just a basic working example.

Example code:

   // Test for control codes

   function isCtrl(aChar)

   {

      myCharCode = aChar.charCodeAt(0);

   

      if(((myCharCode > -1) && (myCharCode <  32)) ||

        ((myCharCode == 127)))

      {

         return true;

      }

   

      return false;

   }