function validateForm(){
 var formCheck = document.getElementsByTagName("input");

   for(n=0; n<formCheck.length; n++){
       if(formCheck[n].type=="checkbox" && formCheck[n].name == "itemnum"){
            if(formCheck[n].checked == true){
                      return true;
            }

       }
   }
   alert("Please select at least one item to add to the cart.");
   return false;
 }