<script type="text/javascript"> //异步请求对象 var xmlRequest; //得到请求对象 function getXMLHttpRequestObject() { //不同的浏览器创建方式不同 try { xmlRequest = new XMLHttpRequest(); //Firefox,safari } catch (e) { //IE try { xmlRequest = new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { xmlRequest = new ActiveXObject("Microsoft.XMLHTTP"); } } return xmlRequest;//返回 } //检查用户是否存在 function checkType(selectType) { alert(selectType); //用户名输入不能为空 if (selectType == "") { document.getElementById("selectType").innerHTML = "<font color='red'> 不能为空!</font>"; return; } //得到请求对象 xmlRequest = getXMLHttpRequestObject(); if (xmlRequest == null) { alert("您的浏览器不支持AJAX!"); return; } var url = "/datacenter/analysisBLOAction.action"; //请求页面 url += "?selectType=" + selectType; //用户名 url = encodeURI(url); url = encodeURI(url); xmlRequest.onreadystatechange = stateChanged;//状态改变调用函数 xmlRequest.open("POST",url,true); //xmlRequest.setRequestHeader('Content-Type','application/x-www-form-urlencoded; charset=UTF-8'); xmlRequest.send(null); // 发送请求 } //是否已经存在检查 function stateChanged() { if (xmlRequest.readyState == 4) { if (xmlRequest.status == 200) { showMess(); } else { //页面不正常 window.alert("您所请求的页面有异常。"); } } else { //请求状态还没有成功,页面等待 document.getElementById("selectType").innerHTML = "检查中..."; } } //检查 异步处理显示信息 function showMess() { var message = xmlRequest.responseText; document.getElementById("selectType").innerHTML = message; } </script>