action向jsp页面传递数据的方法
关键字: struts, request
action向jsp页面传递数据的几种方法：
前提：在struts的配置文件struts-config.xml中，设置该action的scope属性为“request”，即：
Xml代码
<struts-config>
<form-beans>
<form-bean name="loginForm" type="com.bjsxt.struts.LoginActionForm"/>
</form-beans>
<action-mappings>
<action path="/login"
type="com.bjsxt.struts.LoginAction"
name="loginForm"
scope="request"
>
<forward name="success" path="/login_success.jsp"/>
<forward name="error" path="/login_error.jsp"/>
</action>
</action-mappings>
</struts-config>
<struts-config>
<form-beans>
<form-bean name="loginForm" type="com.bjsxt.struts.LoginActionForm"/>
</form-beans>
<action-mappings>
<action path="/login"
type="com.bjsxt.struts.LoginAction"
name="loginForm"
scope="request"
>
<forward name="success" path="/login_success.jsp"/>
<forward name="error" path="/login_error.jsp"/>
</action>
</action-mappings>
</struts-config> 注意：所有struts-config.xml中的path属性都是以"/"开头的。
方法一：在action中利用request对象的setAttribute方法来传递数据
Java代码
package com.bjsxt.struts;
/**
* 用户登录的Action
*/
public class LoginAction extends Action {
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
LoginActionForm laf = (LoginActionForm)form;
String username = laf.getUsername();
String password = laf.getPassword();
String errorInfo = "";
try {
UserManager.getInstance().login(username, password);
//request.setAttribute("username", username);
return mapping.findForward("success");
}catch(UserNotFoundException unfe) {
unfe.printStackTrace();
errorInfo = "用户不能找到，用户名称=[" + username + "]";
}catch(PasswordErrorException pee) {
pee.printStackTrace();
errorInfo = "密码错误";
}
request.setAttribute("errorinfo", errorInfo);
return mapping.findForward("error");
}
}
package com.bjsxt.struts;
/**
* 用户登录的Action
*/
public class LoginAction extends Action {
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
LoginActionForm laf = (LoginActionForm)form;
String username = laf.getUsername();
String password = laf.getPassword();
String errorInfo = "";
try {
UserManager.getInstance().login(username, password);
//request.setAttribute("username", username);
return mapping.findForward("success");
}catch(UserNotFoundException unfe) {
unfe.printStackTrace();
errorInfo = "用户不能找到，用户名称=[" + username + "]";
}catch(PasswordErrorException pee) {
pee.printStackTrace();
errorInfo = "密码错误";
}
request.setAttribute("errorinfo", errorInfo);
return mapping.findForward("error");
}
}
设置好后，就可以在login_success.jsp页面中，利用一下代码得到数据：
Java代码
<%= request.getAttribute("username") %>
<%= request.getAttribute("username") %>
方法二：直接在request对象中获取ActionForm对象：
Html代码
<%@ page import="com.bjsxt.struts.*" %>
<%
LoginActionForm laf = (LoginActionForm)request.getAttribute("loginForm");
%>
<%=laf.getUsername() %>,登录成功