• Struts2方法调用的三种方式(有新的!调用方法的说明)


    在Struts2中方法调用概括起来主要有三种形式

    第一种方式:指定method属性

    <action name="heroAction" class="com.ABC123.HeroAction" method="add">   
                <result name="add">/add.jsp</result>   
            </action>  
    

      这样Struts2就会调用heroAction中的add方法。

    第二种方式:动态方法调用(DMI)

    用这种方法需要设置一个常量

    struts2的2.3以上版本的jar包 必须配置DMI

    <constant name="struts.enable.DynamicMethodInvocation" value="true" /> 
    

      

    <?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">
    <struts> 
    
    	<constant name="struts.enable.DynamicMethodInvocation" value="true" />  
    
    <package name="goToEat" namespace="/" extends="struts-default">
    	
    	<action name="heroAction" class="com.ABC123.action.HeroAction" >
    	<result name="list" >/list.jsp</result>
    	<result name="gotoupd" >/upd.jsp</result>
    	
    	<!-- 重定向-->
    	<result name="add" type="redirect">heroAction!list.action</result>
    	
    	 
    	</action>
    	 
    	</package>
    	
    </struts>    
    

      动态方法调用是指表单元素的action并不是直接等于某个Action的名字,而是以如下形式来指定Form的action属性

    <!-- action属性为action!methodName的形式 -->   
            action = "action!methodName.action"   
    

      在struts.xml中定义如下Action

    <package name="goToEat" namespace="/" extends="struts-default">
    	
    	<action name="heroAction" class="com.ABC123.action.HeroAction" >
    	<result name="list" >/list.jsp</result>
    	<result name="gotoupd" >/upd.jsp</result>
    	
    	<!-- 重定向-->
    	<result name="add" type="redirect">heroAction!list.action</result>
    	
    	 
    	</action>
    	 
    	</package>
    

      HeroAction中的方法为

    package com.ABC123.action;
    
    import java.util.ArrayList;
    import java.util.List;
    
    import com.ABC123.pojo.Hero;
    
    public class HeroAction {
    
    	private static List<Hero> heroList=new ArrayList<Hero>();
    	
    	private  Hero hero;
    	
    	private int id;
    	
    	static{
    		heroList.add(new Hero(1, "德玛", 12, "德玛西亚", "很难哦哦"));
    		heroList.add(new Hero(2, "艾希", 45, "德玛西亚", "很厉害的啊"));
    		heroList.add(new Hero(3, "亚索", 78, "小学生", "很牛逼"));
    	}
    	
    	
    	public  String list() {
    		
    	
    		return "list";
    		
    		
    		
    	}
    	
    	//增加
    	public  String add() {
    		
    		System.out.println(hero);
    		
    		heroList.add(hero);
    		return "add";
    		
    		
    		
    	}
    	
    	//删除
    	public String del() {
    		
    		
    		System.out.println("删除的下标===>"+id);
    		
    		Hero hero2 = heroList.get(id);
    		
    		System.out.println(hero2);
    		
    		heroList.remove(hero2);
    		return "add";
    	}
    	
    	
    	
    	public String goToUpd() {
    		
    		Hero hero5 = heroList.get(id);
    		System.out.println("该条点击修改的的hero==>"+hero5);
    		
    		return "gotoupd";
    		
    		
    		
    	}
    	
    	
    	
    	//修改
    	public String upd() {
    		System.out.println(hero.getId());
    		int id2 = hero.getId();
    		id2-=1;
    		System.out.println("id2===>"+id2);
    		
    		//修改前
    		Hero hero5 = heroList.get(id2);
    		System.out.println("该条点击修改的的hero==>"+hero5);
    		
    	
    		
    		//接到的值为hero
    		
    		hero5.setAge(hero.getAge());
    		
    		hero5.setName(hero.getName());
    		
    		hero5.setStory(hero.getStory());
    		
    		hero5.setZhenying(hero.getZhenying());
    		
    //		heroList.set(id2, hero);
    		
    		
    		System.out.println("修改后的hero==>"+hero);
    		return "add";
    	}
    	
    	
    	//================================
    
    	public List<Hero> getHeroList() {
    		return heroList;
    	}
    
    	public void setHeroList(List<Hero> heroList) {
    		this.heroList = heroList;
    	}
    
    	public Hero getHero() {
    		return hero;
    	}
    
    	public void setHero(Hero hero) {
    		this.hero = hero;
    	}
    
    	public int getId() {
    		return id;
    	}
    
    	public void setId(int id) {
    		this.id = id;
    	}
    
    	
    
    	
    	
    	
    	
    	
    	
    }
    

      则在JSP中用如下方式调用方法

    <%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
        <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
        <%@ taglib uri="/struts-tags" prefix="s" %>
    <!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=UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    <a href="/struts-01/add.jsp">去添加</a>
    </br>
    </br>
    <table border="1">
    	<tr>
    		<td>id</td>
    		<td>name</td>
    		<td>age</td>
    		<td>zhenying</td>
    		<td>story</td>
    			<td colspan="2">操作</td>
    	</tr>
    	
    	<c:forEach items="${heroList }" var="hero">
    	<tr>
    		<td>${hero.id }</td>
    		<td>${hero.name }</td>
    		<td>${hero.age }</td>
    		<td>${hero.zhenying }</td>
    		<td>${hero.story }</td>
    		<td><a href="heroAction!goToUpd.action?id=${hero.id -1}">修改</a></td>
    	<td><a href="heroAction!del.action?id=${hero.id -1 }">删除</a></td>
    	</tr>
    	</c:forEach>
    </table>
    
    <hr>
    
    <a href="/struts-01/add.jsp">去添加</a>
    </br>
    </br>
    <table border="1">
    	<tr>
    		<td>id</td>
    		<td>name</td>
    		<td>age</td>
    		<td>zhenying</td>
    		<td>story</td>
    		<td colspan="2">操作</td>
    	</tr>
    	
    	<s:iterator value="heroList">
    	
    	<tr>
    		<td><s:property value="id"/></td>
    		<td><s:property value="name "/></td>
    		<td><s:property value="age "/></td>
    		<td><s:property value="zhenying "/></td>
    		<td><s:property value="story "/></td>
    	<td><a href="heroAction!goToUpd.action?id=<s:property value='id-1'/>">修改</a></td>
    	<td><a href="heroAction!del.action?id=<s:property value='id-1'/>">删除</a></td>
    	</tr>
    	</s:iterator>
    
    </table>
    
    </body>
    </html>
    

      第三种方式:通配符(推荐使用)

    <action name="heroAction_*" class="com.ABC123.action.HeroAction" method="{1}">
    	<result name="list" >/list.jsp</result>
    	</action>
    

      这里的{1} 相当于传进来字符串进行拼接地址 比如传进来list 拼接为/list.jsp

    <action name="heroAction_*" class="com.ABC123.action.HeroAction" method="{1}">
    	<result name="{1}" >/{1}.jsp</result>
    	</action>
    

      

    <a href="heroAction_list.action">查询
    <a href="heroAction_add.action">增加
    

      

    heroAction_list.action就会调用heroAction中的list方法 然后跳转到list.jsp
    heroAction_add.action就会调用heroAction中的add方法 然后跳转到add.jsp

     

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  • 原文地址:https://www.cnblogs.com/charlypage/p/8894132.html
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