Use jquery. validationengine ajax to verify whether the background ID already exists
Front-end jquery validation framework Verification
JSP:
<link rel="stylesheet" type="text/css" href="<%=path%>/js/css/validationEngine.jquery.css"/><script type="text/javascript" src="<%=path%>/js/jquery/jquery-1.4.2.min.js"></script><script type="text/javascript" src="<%=path%>/js/validation/jquery.validationEngine-cn.js"></script><script type="text/javascript" src="<%=path%>/js/validation/jquery.validationEngine.js"></script> <input type="text" name="item.entry" id="item_entry" class="validate[required,custom[onlyNumber],ajax[ajaxItemNoCall],length[0,4]] text-input" size="10"/></td>
Jquery. validationEngine-cn.js
"Ajaxitemnocall": {"url": "validateitemno", "alerttext": "* ID used", "alerttextok": "* ID can be used", "alerttextload ": "* Checking. Please wait... "}
Itemaction. Java
@ Action (Results = {@ result (type = "JSON")}, Params = {"excludeproperties", "validatereturn"}, value = "validateitemno") Public String validateitemno () throws exception {actioncontext Ct = actioncontext. getcontext (); httpservletrequest request = (httpservletrequest) CT. get (servletactioncontext. http_request); string validateid = request. getparameter ("fieldid"); string validatevalue = request. getparameter ("F Ieldvalue "); int valivalue = integer. parseint (validatevalue); item = itemservice. finditembyid (valivalue); If (item. getentry ()! = Valivalue) {validatereturn [0] = validateid; validatereturn [1] = true; validatereturn [2] = "available";} else {validatereturn [0] = validateid; validatereturn [1] = false; validatereturn [2] = "the specified ID already exists";} return "success ";}