OGNL的相关知识

来源：互联网发布：淘宝充值卡代理编辑：程序博客网时间：2024/05/17 06:48

本文主要介绍了struts2的OGNL表达式的强大功能

<%@ page language="java" contentType="text/html; charset=utf-8"    pageEncoding="utf-8"%>    <%@taglib prefix="s"  uri="/struts-tags"%><!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Insert title here</title><script>window.onload=function(){var a='<s:property value="a"/>';}</script></head><body><%request.setAttribute("p", "pppppp"); pageContext.setAttribute("r", "rrrrrrrr");%><s:property value="uname"/><s:property value="user.addr.city"/><hr/>actionContext的值:<s:property value="a"/><hr/>request的值:<s:property value="#request.b"/>另一种写法1:<s:property value="#request['b']"/>另一种写法2:<s:property value="#request[#parameters.a[0]]"/><hr/>session的值:<s:property value="#session.c"/><hr/>appliaction的值:<s:property value="#application.d"/><hr/>parameters的值:<s:property value="#parameters.a[0]"/><hr/>attr的值:<s:property value="#attr.b"/><s:property value="#attr.p"/><s:property value="#attr.r"/><hr>运算:<s:property value="2+4"/>赋值:<s:property value="#request.p=123"/>赋值后:<s:property value="#request.p"/><hr>OGNL操作集合<s:set var="list" value="{'a','b','c'}" scope="request"></s:set>list集合的值:<s:property value="#request.list.get(2)"/><hr>判断：<s:property value="'a' in #request.list"/>判断：<s:property value="'a' not in #request.list"/><hr><s:set var="map" value="#{'name':'zxs','age':#request.list.get(2)}" scope="request"></s:set>map集合的值:<s:property value="#request.map.age"/>判断：<s:property value="'age' in #request.map.keys"/>判断：<s:property value="'c'      in  #request.map.values"/><hr>遍历:<s:iterator value="#request.list"  var="temp"><s:property value="#temp"/></s:iterator><hr>调用方法:获取PI的值:<s:property value="@@PI"/><s:debug></s:debug></body></html>

package com;import java.util.Map;import bean.Address;import bean.User;import com.opensymphony.xwork2.ActionContext;import com.opensymphony.xwork2.ActionSupport;public class TestOgnlContext extends ActionSupport{private User user;private String uname;public String test1() throws Exception{setUname("zhangxiaosheng");User u=new User(1,"zxs","123456");u.setAddr(new Address("china","shanghai","changning"));setUser(u);ActionContext ac=ActionContext.getContext();ac.put("a", "actionContext的值");((Map)(ac.get("request"))).put("b","request的值");((Map)(ac.get("session"))).put("c","session的值");((Map)(ac.get("application"))).put("d","appliaction的值");return SUCCESS;}public User getUser() {return user;}public void setUser(User user) {this.user = user;}public String getUname() {return uname;}public void setUname(String uname) {this.uname = uname;}}

测试结果如图:

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