Get current cursor position in a textbox

javascript firefox textbox cursor
Perseus picture Perseus · Apr 19, 2013 · Viewed 118.2k times · Source

I need a code to find current position of cursor in a textbox/textarea. It should work with chrome and firefox. Following is the code which I am using:

<!DOCTYPE html>
<html>
  <head>
    <script>
      function textbox()
      {
        document.getElementById('Javascript_example').value = document.activeElement.id;
        var ctl = document.getElementById('Javascript_example');
        alert(ctl);

        var startPos = ctl.selectionStart;
        alert(startPos);
        var endPos = ctl.selectionEnd;
        alert(endPos);
      }
    </script>
  </head>
  <body>

    <input id="Javascript_example" name="one" type="text" value="Javascript_example" onclick="textbox()">

  </body>
</html>

Any suggestion?

Answer

Tim Down picture Tim Down · Apr 19, 2013

It looks OK apart from the space in your ID attribute, which is not valid, and the fact that you're replacing the value of your input before checking the selection.

function textbox()
{
        var ctl = document.getElementById('Javascript_example');
        var startPos = ctl.selectionStart;
        var endPos = ctl.selectionEnd;
        alert(startPos + ", " + endPos);
}
<input id="Javascript_example" name="one" type="text" value="Javascript example" onclick="textbox()">

Also, if you're supporting IE <= 8 you need to be aware that those browsers do not support selectionStart and selectionEnd.

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