checkUsername.jsp的代码
<%@ page language="java" pageEncoding="UTF-8"%>
<%
response.setContentType("text/xml");
response.setHeader("Cache-Control","no-cache");
String username=request.getParameter("username");
boolean is Valid=false;
if(username.equals("admin")){
is Valid=true;
}
if(is Valid){
out.println("<content>该用户名已经存在！</content>");
}
else{
ut.println("<content>ok</content>");
}
%>
html代码
<!DOCTYPE HTML PUBLIC"_//W3C//DTD HTML4.01 Transitional//EN">
<html>
<head>
<title></title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="">
<meta http-equiv="description" content="">
<meta http-equiv="Content-Type" content="text/html;charset=gb2312">
<script>
var XMLHttpReq=false;
function createXMLHttpRequest(){
if(window.XMLHttpRequest){
XMLHttpReq=new XMLHttpRequest();
}
else if(window.ActiveXObject){
try{
XMLHttpReq=new ActiveXObject("Msxml2.XMLHTTP");
}catch(e){
try{
XMLHttpReq=new ActiveXObject("Microsoft.XMLHTTP");
}catch(e){}
}
}
}
function send(url){
createXMLHttpRequest();
XMLHttpReq.open("GET",url,true);
XMLHttpReq.onreadystatechange=parse;
XMLHttpReq.send(null);
}
function parse(){
if(XMLHttpReq.readyState==4){
if(XMLHttpReq.status==200){
var res=XMLHttpReq.responseXML.getElementsByTagName("content")[0].firstChild.data;
if(res=="ok"){
document.getElementById("status").innerHTML="该用户名可以使用！";
}
else{document.getElementById("status").innerHTML=res;
window.alert(res);}
}else{window.alert("所请求的页面异常");}
}
}
function checkUsername(){
var username=document.getElementById("username").value;
if(username==""){
alert("请输入用户名！");
return false;
}else{
send('action/checkUsername.jsp?username='+username);
}
}
</script>
</head>
<body bgcolor="#9393FF" link="#272727" vlink="#BF0060" alink="#930093">
<table height="100%" width="100%">
<tr>
<td align="center">
<table width="807" height="675" background="注册.jpg">
<tr>
<td width="10%"></td>
<td>
<form name="form1" action="11.jsp" method="post"
>
<table width="300" boder="0">
<tr>
<td colspan="2">
<div id="status"><font size=6>注册新用户</font></div>
</td>
<tr>
<td><font size=5>*用户名</font></td>
<td><input type="text" name="username" size=15 maxlength="10" value="" onblur="checkUsername();" ></td>
</tr>
<tr>
<td><font size=5>*密码</font></td>
<td><input type="password" name="password1" size=15 maxlength="17" value="" ></td>
</tr>
<tr>
<td colspan="2"><a href="login.jsp"><font size=5><u>返回登录页</u></font></a><input type="image" width="100" height="30"
src="E:\eclipse\workspace\jsp\WebContent\按钮.gif
" onClick="check()">
<script language="javascript">
function check()
{
document.form.submit();
}
</script>
</td>
</tr>
</tr>
</table>
</form>
</td>
</tr>
</table>
</td>
</tr>
</table>
</body>
</html>