52,797
社区成员
发帖
与我相关
我的任务
分享
jsp中的代码:
script type="text/javascript">
var xmlHttp=false;
function createXMLHttpRequest() {
if (window.ActiveXObject) {
xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
}
else{
xmlHttp = new XMLHttpRequest();
}
}
function checkUser() {
document.getElementById("spCheckUser").style.color = "green";
document.getElementById("spCheckUser").innerHTML="自动检测用户名...";
createXMLHttpRequest();
xmlHttp.onreadystatechange = callback;
var strUser = document.getElementsByName("username")[0].value;
url="/AjaxTest?strUser="+strUser;
xmlHttp.open("GET", url , true);
xmlHttp.send(null);
}
function callback() {
if (xmlHttp.readyState == 4 ){
if (xmlHttp.status == 0 || xmlHttp.status == 200){
var messageArea = document.getElementById("spCheckUser");
if (xmlHttp.responseText == "false") {
messageArea.innerHTML = "该用户名还没有被占用,您可以注册";
}
else{
messageArea.style.color = "red";
messageArea.innerHTML = "该用户名已经被占用";
}
}
}
}
</script>
</head>
<body>
username:<input type="text" name="username" id="username" size="20" onblur="checkUser();"/><span id="spCheckUser" style="color:red;"></span><br />
password:<input type="password" size="20" />
</body>
</html>
servlet中的代码:
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
this.doPost(req, resp);
}
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
String str = req.getParameter("strUser");
resp.setContentType("text/xml;charset=utf-8");
resp.setHeader("Cache-Control", "no-cache");
boolean responseText = this.isUserExist(str);
PrintWriter out=resp.getWriter();
out.println(responseText);
out.close();
}
public boolean isUserExist(String username){
if(username.equals("ddd")){
return true;
}
else{
return false;
}
}
boolean responseText = this.isUserExist(str);
PrintWriter out=resp.getWriter();
out.println(responseText);
String User_Name= req.getParameter("strUser");
resp.setContentType("text/xml;charset=utf-8");
resp.setHeader("Cache-Control", "no-cache");
PrintWriter out=resp.getWriter();
if(User_Name.equals("ddd")){
out.println("false");
}
else{
out.println("true");
}
out.close();
public boolean isUserExist(String username){
if(username.equals("ddd")){
return true;
}
else{
return false;
}
}
public boolean isUserExist(String username){
if(username.equals("ddd")){
out.println("true");
}
else{
out.println("false");
}
}