ASCII control character html input text

Question

I\'m trying to process input from a barcode scanner in a javascript browser app. The scanner output is a string of characters, which also contains at least one Group Separator c

Answer 1

The input control ignores non printable characters like [GS]

However, a barcode scanner usually emulates this character with CTRL+], which can be captured with the onkeydown event (key codes 17 and 221):

    var ctrlPressed = false;
    yourInput.addEventListener('onkeydown', function (event) {
       ctrlPressed = 17 === event.keyCode;
       if (221 === event.keyCode && ctrlPressed)
          // do what you want here (ie. modify the input value)
    });

If this does not work you may want to check the codes first by logging them:

    yourInput.addEventListener('onkeydown', function (event) {
      console.log(event.keyCode)
    });