Setting Cursor Position in TextBox with Javascript

function setCaretPosition(elemId, caretPos) {
  var elem = document.getElementById(elemId);

  if(elem != null) {
      if(elem.createTextRange) {
          var range = elem.createTextRange();
          range.move('character', caretPos);
          range.select();
      }
      else {
          if(elem.selectionStart) {
              elem.focus();
              elem.setSelectionRange(caretPos, caretPos);
          }
          else
              elem.focus();
      }
  }
}

The first expected parameter is the ID of the element you wish to insert the cursor on. If the element is unable to be found, nothing will happen (obviously). The second parameter is the caret positon index. Zero will put the cursor at the beginning. If you pass a number larger than the number of characters in the elements value, it will put the cursor at the end.