ajax的get、post验证用户名
1.register_get.html(get方法提交)
<html><head>
<meta charset="UTF-8">
<title>用户注册</title>
<script type="text/javascript">
<!--创建ajax引擎验证用户名是否存在-->
function getSend() {
//xmlhttprequest对象
var xmlhttp;
if (window.XMLHttpRequest) {// IE7+, Firefox, Chrome, Opera, Safari 浏览器执行代码
xmlhttp = new XMLHttpRequest();
} else { // IE6, IE5 浏览器执行代码
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); }
//验证用户名是否存在
if (xmlhttp) {
var user = document.getElementById("username").value;
alert(user);
var url = "registerProcess.jsp?username=" + user;
//var url="registerProcess.jsp?myTime="+new Date()+"&username="+user;
xmlhttp.open("GET", url, true);
//myXmlHttpRequest.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
//回调函数
xmlhttp.onreadystatechange = function() {
alert(xmlhttp.readyState + ":" + xmlhttp.status);
if (xmlhttp.readyState == 4)
document.getElementById("yanzheng").innerHTML = xmlhttp.responseText; }
xmlhttp.send(null); } }
</script></head><body>
<form action="???" method="post">
username<input type="text" id="username" name="username"> <input
type="button" οnclick="getSend()" value="验证"><span
style="color: red" id="yanzheng"></span><br>
</form></body></html>
2.register_post.html(post方法提交)
<!DOCTYPE html>
<html><head>
<meta charset="UTF-8">
<title>Insert title here</title>
<script type="text/javascript">
//创建对象
function getXmlhttpRequest(){
var xmlHttpRequest;
if (window.XMLHttpRequest)
{// IE7+, Firefox, Chrome, Opera, Safari 浏览器执行代码
xmlHttpRequest=new XMLHttpRequest(); }
else { // IE6, IE5 浏览器执行代码
xmlHttpRequest=new ActiveXObject("Microsoft.XMLHTTP"); }
return xmlHttpRequest;}
//验证用户名
var myXmlHttpRequest="";
function checkName() {
myXmlHttpRequest=getXmlhttpRequest();
if(myXmlHttpRequest){
var url="registerProcess.jsp";
var data="username="+document.getElementById("username").value;
alert("data:"+data);
myXmlHttpRequest.open("post",url,true);
myXmlHttpRequest.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
myXmlHttpRequest.onreadystatechange=function(){
alert(myXmlHttpRequest.readyState);
if (myXmlHttpRequest.readyState==4)
document.getElementById("yanzheng").innerHTML=myXmlHttpRequest.responseText;}
myXmlHttpRequest.send(data); }}
</script></head><body>
<form action="#" method="post">
username<input type="text" id="username" name="username"><span style="color:red" id="yanzheng"></span><br>
<input type="button" οnclick="checkName()" value="验证"><br>
</form></body></html>
3.RegisterProcess.jsp(发出ajax请求的JSP页面)
<%@ page language="java" contentType="text/html; charset=GB18030" pageEncoding="GB18030"%>
<body>
<%request.setCharacterEncoding("utf-8");
String username=request.getParameter("username");
System.out.println(username+" ");
out.print(username);
if(username.equals("lx")) out.print("用户名不可用 ");
else out.print("用户名可用");%>
</body>
结果分析: