// isInteger -----------------------------------------------------------------------------
  function isInteger(theElement, theElementName)
  {
    var s = Math.abs(theElement.value);
    var filter=/(^\d+$)/;
    if (s.length == 0 ) return true;
    if (filter.test(s))  
         return true;
    else  
           alert(alert_isinteger_mesg);
      theElement.focus(); 
      return false;
  }
//----------------------------------------------------------------------------------------