struts2框架下用ajax 总是404错误

这是调用的action

 xmlHttp.open("post","/baidu/StuNoCheck.action?stuNo=" + stuNo,true);             xmlHttp.send(null);         }         function checkStuNoCallback(){         alert(“11”);             if(xmlHttp.readyState == 4){             alert(xmlHttp.status);                 if(xmlHttp.status == 200){                     var text = xmlHttp.responseText;  论文网 

正常能打印出11  说明就是调用不到我的action
下面试我struts2xml的配置  而且运行时什么错也不报

 <package name="myFirst" namespace="/baidu" extends="struts-default"> <action name="StuNoCheck" class="com.dxy.action.StuNoCheck">  <result name="success">/StudentManager/StudentManager.jsp</result>          </action>

路径问题，
改为
xmlHttp.open("post","${pageContext.request.contextPath}/baidu/StuNoCheck.action?stuNo=" + stuNo,true);
或者
xmlHttp.open("post","baidu/StuNoCheck.action?stuNo=" + stuNo,true);