上节我们利用List集合来封装多个地址信息，其实把List集合换成Map集合也是可以的。下面，看看Spring MVC如何使用Map集合类型封装表单参数？
1 设计表单
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>一点教程网 - www.yiidian.com</title>
</head>
<body>
<h2>Map集合类型参数封装</h2>
<form action="/param.do" method="post">
用户名：<input type="text" name="username"><br>
年龄：<input type="text" name="age"><br>
省份1：<input type="text" name="address['a1'].province"><br>
城市1：<input type="text" name="address['a1'].city"><br>
省份2：<input type="text" name="address['a2'].province"><br>
城市2：<input type="text" name="address['a2'].city"><br>
<input type="submit" value="提交">
</form>
</body>
</html>
注意：这里的address['a1'].city，a1是赋值给Map的key，city是赋值给Address的city属性
2 设计Pojo
Address对象：
package com.yiidian.domain;
/**
* 封装用户的地址信息
* 一点教程网 - www.yiidian.com
*/
public class Address {
private String province;
private String city;
public String getProvince() {
return province;
}
public void setProvince(String province) {
this.province = province;
}
public String getCity() {
return city;
}
public void setCity(String city) {
this.city = city;
}
@Override
public String toString() {
return "Address{" +
"province='" + province + '\'' +
", city='" + city + '\'' +
'}';
}
}
User对象：
package com.yiidian.domain;
import java.util.List;
import java.util.Map;
/**
* 用于封装表单数据
* 一点教程网 - www.yiidian.com
*/
public class User {
private String username;
private Integer age;
private Map<String,Address> address;//这里使用Map集合接收表单多个地址信息
public Map<String, Address> getAddress() {
return address;
}
public void setAddress(Map<String, Address> address) {
this.address = address;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
@Override
public String toString() {
return "User{" +
"username='" + username + '\'' +
", age=" + age +
", address=" + address +
'}';
}
}
在User对象使用Map集合来封装多个地址信息
3 编写Controller
package com.yiidian.controller;
import com.yiidian.domain.Address;
import com.yiidian.domain.User;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import java.util.Map;
/**
* Map集合参数封装
* 一点教程网 - www.yiidian.com
*/
@Controller
public class ParamController {
@RequestMapping("/param.do")
public String save(User user){
System.out.println("用户名："+user.getUsername());
System.out.println("年龄："+user.getAge());
//遍历所有地址信息
Map<String, Address> address = user.getAddress();
for(Map.Entry entry:address.entrySet()){
System.out.println(entry.getKey()+"--"+entry.getValue());
}
return "success";
}
}
4 springmvc.xml配置
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 1.扫描Controller的包-->
<context:component-scan base-package="com.yiidian.controller"/>
<!-- 2.配置视图解析器 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!-- 2.1 页面前缀 -->
<property name="prefix" value="/pages/"/>
<!-- 2.2 页面后缀 -->
<property name="suffix" value=".jsp"/>
</bean>
<!-- 3.创建处理器适配器和处理器映射器-->
<mvc:annotation-driven/>
</beans>
5 运行测试
控制台输出：
