$(document).ready(function(){
  $("form:has(.requiredInput,.requiredCheckbox)").submit(function(){
    /*$("input[type='submit']",this).click(function(){
      $(this).attr("disabled", "disabled");
    });*/
  
    var validResult = true;
    $(".requiredInput",this).each(function(){
      if(jQuery.trim($(this).val()) == "" && validResult == true){
        alert("Please fill in all required fields.");
        $(this).focus();
        validResult = false;
      }
    });
    if(validResult && $(".requiredCheckbox",this).length > 0){
      var oneChecked = false;
      $(".requiredCheckbox",this).each(function(){     
        if($(this).is(':checked')){
          oneChecked = true;
        }
      }); 
      if(!oneChecked){
        alert("Please check at least one box.");
        validResult = false;
      }   
    }
    /*if(!validResult){
      $("input[type='submit']",this).removeAttr('disabled');
    }*/
    return validResult;  
  });
  
  $("input[type='file']",this).after(" <input type=\"button\" class=\"clearbtn\" value=\"Clear\">");
  $(".clearbtn").click(function(){       
    $(this).prev().val("");
  });
});