笔记17 接受表单数据

场景描述：

　　　　用户提交产品名称和价格到Spring MVC Spring MVC接受数据并显示

1.实体类Product.java

 1 package pojo;
 2 
 3 public class Product {
 4     private int id;
 5     private String name;
 6     private float price;
 7 
 8     public int getId() {
 9         return id;
10     }
11 
12     public void setId(int id) {
13         this.id = id;
14     }
15 
16     public String getName() {
17         return name;
18     }
19 
20     public void setName(String name) {
21         this.name = name;
22     }
23 
24     public float getPrice() {
25         return price;
26     }
27 
28     public void setPrice(float price) {
29         this.price = price;
30     }
31 }

2.增加商品的页面addProduct.jsp

　　在web目录下（不是在WEB-INF下）增加商品的页面addProduct.jsp

 1 <%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
 2 <%
 3 String path = request.getContextPath();
 4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
 5 %>
 6 
 7 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 8 <html>
 9   <head>
10     <base href="<%=basePath%>">
11     
12     <title>My JSP 'addProduct.jsp' starting page</title>
13     
14     <meta http-equiv="pragma" content="no-cache">
15     <meta http-equiv="cache-control" content="no-cache">
16     <meta http-equiv="expires" content="0">    
17     <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
18     <meta http-equiv="description" content="This is my page">
19     <!--
20     <link rel="stylesheet" type="text/css" href="styles.css">
21     -->
22 
23   </head>
24   
25   <body>
26     <h1 align="center">增加商品</h1>
27     <form action="addProduct">
28         产品名称：<input type="text" name="name" vlaue=""><br>
29         产品价格：<input type="text" name="price" vlaue=""><br>
30         <input type="submit" value="增加商品">
31     </form>
32   </body>
33 </html>

3.控制器类ProductController

控制器ProductController，准备一个add方法映射/addProduct路径

为add方法准备一个Product 参数，用于接收注入

最后跳转到showProduct页面显示用户提交的数据

注： addProduct.jsp 提交的name和price会自动注入到参数 product里
注：参数product会默认被当做值加入到ModelAndView 中，相当于：

mav.addObject("product",product);

 1 package pojo;
 2 
 3 import org.springframework.stereotype.Controller;
 4 import org.springframework.web.bind.annotation.RequestMapping;
 5 import org.springframework.web.servlet.ModelAndView;
 6 
 7 @Controller
 8 public class ProductController {
 9 
10     @RequestMapping("/addProduct")
11     public ModelAndView add(Product product) throws Exception {
12         ModelAndView mav = new ModelAndView("showProduct");
13         return mav;
14     }
15 
16 }

4.显示商品的界面showProduct.jsp

在WEB-INF/page 目录下创建 showProduct.jsp
用 EL 表达式显示用户提交的名称和价格

 1 <%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
 2 <%
 3 String path = request.getContextPath();
 4 String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
 5 %>
 6 
 7 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 8 <html>
 9   <head>
10     <base href="<%=basePath%>">
11     
12     <title>My JSP 'showProduct.jsp' starting page</title>
13     
14     <meta http-equiv="pragma" content="no-cache">
15     <meta http-equiv="cache-control" content="no-cache">
16     <meta http-equiv="expires" content="0">    
17     <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
18     <meta http-equiv="description" content="This is my page">
19     <!--
20     <link rel="stylesheet" type="text/css" href="styles.css">
21     -->
22 
23   </head>
24   
25   <body>
26     <h1 align="center">商品信息</h1>
27     产品名称：${product.name}<br>
28     产品价格：${product.price}
29   </body>
30 </html>

5.测试

目录结构：