Getting Deleted character

Question

in in Input field, if the user presses Backspace or Delete key, is there a way to get the deleted character.

I need to check it against a RegExp.

Answer 1

Assuming the input box has an id 'input'. Here is how with least amount of code you can find out the last character from the input box.

document.getElementById("input").onkeydown = function(evt) {
  const t = evt.target;
  if (evt.keyCode === 8) { // for backspace key
    console.log(t.value[t.selectionStart - 1]);
  } else if (evt.keyCode === 46) { // for delete key
    console.log(t.value[t.selectionStart]);
  }
};

<input id="input" />