J2EE的ajax用户注册验证

 

这个应用主要用在springside框架中的ajax用户注册验证,我这个菜鸟做的大家试试参考!!

1页面jsp 的script代码:

 

<script type="text/javascript">

    var xmlHttp;

 

 

 

    function createXMLHttpRequest() {

 

    if (window.ActiveXObject) {

 

        xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");

 

    }

 

    else if (window.XMLHttpRequest) {

 

        xmlHttp = new XMLHttpRequest();

 

    }

 

    }

   

    function createQueryString() {

 

    var userid = document.getElementById("userid").value;

    var queryString = "userid=" + userid;

 

     

   

    return queryString ;

 

    }

   

   

    function doRequestUsingGET() {

    if(document.getElementById("userid").value==""){

       alert("用户名不能为空");

      

    }else{

    createXMLHttpRequest();

    var queryString = "<%=request.getContextPath()%>/pages/um/operInfo.do?method=checkuser&";

 

    queryString = queryString + createQueryString()

 

        + "&timeStamp=" + new Date().getTime();

 

    xmlHttp.onreadystatechange = handleStateChange;

 

    xmlHttp.open("GET", queryString, true);

 

    xmlHttp.send(null);

    }

    }

   

    function handleStateChange() {

 

    if(xmlHttp.readyState == 4) {

 

        if(xmlHttp.status == 200) {

 

            parseResults();

 

        }

 

    }

 

    }

 

 

 

    function parseResults() {

 

    var responseDiv = document.getElementById("serverResponse");

 

    if(responseDiv.hasChildNodes()) {

 

        responseDiv.removeChild(responseDiv.childNodes[0]);

 

    }

 

    var responseText = document.createTextNode(xmlHttp.responseText);

 

    responseDiv.appendChild(responseText);

 

    }

 

   

   

 

   

    </script>

 

 

2还要在页面添加一个按钮和一个div层

 

<html:text property="userid" styleClass="text" />

<td width="8%">

<input type="button" value="检查用户" class="MyButton" onclick="doRequestUsingGET();"/>

</td>

<td width="10%" style="color: #FF0000" align="left"><div id="serverResponse"></div>      //当服务端返回值就在这里显示是否存在用户名 

</td>

 

3在ACTION中写一个方法命名为checkuser,记得不要写actionforwad的方法!

/*

     * 验证用户是否存在

     */

    publicvoid checkuser(ActionMapping mapping,ActionForm form,HttpServletRequest request,HttpServletResponse response){

       String userid=request.getParameter("userid");

 

        response.setContentType("text/xml;charset=UTF-8");

        String responseText=null;

      

            try {

              PrintWriter out= response.getWriter();

              int Result=sysUserManager.findUserBy(userid.trim());

              switch(Result)

              {

              case 0:

                  responseText ="该用户名已经存在!";

                  break;

              case 1:

                  responseText ="用户名可以注册!";

                  break;

              }

               out.println(responseText);

               out.close();

           } catch (IOException e) {

              // TODO Auto-generated catch block

              e.printStackTrace();

           }

 

4 在业务层MANAGER类中 findUserBy ()方法

publicint findUserBy(String userid){

      

       SysUser user = null;

       try{

           user = this.get(SysUser.class,userid);

       }catch (Exception e){

          

           user = null;

       }

       if (user==null)

           return 1;

       else

           return 0;    

}