Confirmation popup message when someone clicks a button

Some simple javascript to prompt the user when they click a submit button:

onclick="return confirm('Are you sure you want to delete?');"

UPDATE:   this also works:


 function ConfirmDelete()
      var x = confirm("Are you sure you want to delete?");
      if (x)
          return true;
        return false;

<input style='width:200px;height:40px;' type="submit" Onclick="return ConfirmDelete();" value="Delete" name="mysubmitdelete">