function searchsubmit() {
  var fH=document.getElementById("frm_Search");
  var format = /^2[0-9]{3}-[0-9]{1,2}-[0-9]{1,2}$/;

  if (fH.arrivalDate.value.length==0){alert("Please input you check-in date!");return false;}
  if (!format.test(fH.arrivalDate.value)){alert("Check-in date format type should be: YYYY-MM-DD,please check your date format!");return false;}
  if (fH.departureDate.value.length==0){alert("Please input you check-out date!");return false;}
  if (!format.test(fH.departureDate.value)){alert("Check-out date format type should be: YYYY-MM-DD,please check your date format!");return false;}

  return true;
}