如何利用EL表达式获取list，map，对象等值

Posted 2020-11-12 newcityboy

tags:

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<%@ page import="com.hopetesting.domain.User" %>
<%@ page import="java.util.*" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>el表达式获取对象属性</title>
</head>
<body>
<h1>el设置对象是属性</h1>
<%
    User user = new User();
    user.setName("zmy");
    user.setAge(11);
    user.setBirthday(new Date());
    request.setAttribute("user", user);

    List list = new ArrayList();
    list.add("aaa");
    list.add("bbb");
    list.add(user);
    request.setAttribute("list",list);

    Map map = new HashMap();
    map.put("sname","light");
    map.put("gender","male");
    map.put("user",user);
    request.setAttribute("map",map);

%>
<h1>el获取对象属性</h1>

    ${requestScope.user}<br/>
    ${requestScope.user.name}<br/>
    ${user.age}<br/>
    ${user.birStr}


<h1>el获取list值</h1>
${list[0]}<br/>
${list[1]}<br/>
${list[10]}<br/>
${list[2].name}<br/>

<h1>el获取Map值</h1>
${map.sname}<br/>
${map.gender}<br/>
${map.user.birStr}<br/>


</body>
</html>

package com.hopetesting.domain;

import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * @author newcityman
 * @date 2019/9/6 - 21:00
 */
public class User {
    private String name;
    private Integer age;
    private Date birthday;

    public User() {
    }

    public User(String name, Integer age, Date birthday) {
        this.name = name;
        this.age = age;
        this.birthday = birthday;
    }

    public String getName() {
        return name;
    }

    public Integer getAge() {
        return age;
    }

    public Date getBirthday() {
        return birthday;
    }

    public String getBirStr(){
        if(birthday!=null){
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            return  sdf.format(birthday);
        }else{
            return  "";
        }

    }
    public void setName(String name) {
        this.name = name;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public void setBirthday(Date birthday) {
        this.birthday = birthday;
    }

    @Override
    public String toString() {
        return "User{" +
                "name=‘" + name + ‘‘‘ +
                ", age=" + age +
                ", birthday=" + birthday +
                ‘}‘;
    }
}

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