function selectAll(elementId) {
  var element = document.getElementById(elementId);
  if ( document.selection ) {
    var range = document.body.createTextRange();
    range.moveToElementText(element);
    range.select();
  } else
  if ( window.getSelection ) {
    var range = document.createRange();
    range.selectNodeContents(element);
    var blockSelection = window.getSelection();
    blockSelection.removeAllRanges();
    blockSelection.addRange(range);
  } else {
  	    alert( 'Dein Browser unterstützt diese Funktion leider nicht.' );
  }
  return false;
}