dwr笔记二之经典用法之和spring结合＋验证用户是否存在

spring mvc＋ＤＷＲ验证用户名是否存在，是最经典的案例了．
 
１　在ＤＷＲ２里，注意配置的类名跟ＤＷＲ１不同了
 　　　　由 uk.ltd.getahead 变成了 org.directwebremoting 。
         换上了新的配置
1<servlet>
2    <servlet-name>dwr-invoker</servlet-name>
3    <servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class>
4    <init-param>
5      <param-name>debug</param-name>
6      <param-value>true</param-value>
7    </init-param>
8    <load-on-startup>1</load-on-startup>
9</servlet>
 2  DTD也要改下了
 　　　　<!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 2.0//EN" "http://getahead.org/dwr/dwr20.dtd">
３　dwr.xml
     <?xml version="1.0" encoding="UTF-8"?>
 <!-- <!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 1.0//EN" "http://www.getahead.ltd.uk/dwr/dwr10.dtd">-->
 <!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 2.0//EN" "http://getahead.org/dwr/dwr20.dtd">
 <dwr>
  <allow>
   <convert converter="bean" match="liao.*"/>
   <create creator="spring" javascript="MemberManager">
           <param name="beanName" value="userFacade"/>
         </create>
  </allow>
 </dwr>
    其中userFacade就是spring里面的了．对应一个具体的校验类了
 　４　ＪＳＰ页面端
 　　　function checkRepeat(s) {
     var o = getElement(s);
      if(o.value==""){
       msgs[0].innerHTML="会员名不能为空！";
    o.focus();
    return false; 
      }
      
         if (o) {
             MemberManager.getMemberForName(o.value, showResult);
         }　　　
<SCRIPT language=javascript>
   var msgs = document.getElementsByName("msg");
     var springmsgs = document.getElementsByName("springmsgs");
     function showResult(b) {
      var username = getElement("username").value;
      var usernamemsg = document.getElementsByName("usernamemsg");
         if (b) {
          springmsgs[0].innerHTML="";
          msgs[0].innerHTML="对不起！你正准备注册的 "+username+" 已经被注册，请更换另外的会员名。";
          
         } else {
          usernamemsg.innerHTML="";
          msgs[0].innerHTML="恭喜你！你可以注册 "+username+" 这个会员名。";
         }
     }