1 Result jump method
1ModelAndView
Set the ModelAndView object, and jump to the specified page according to the name of the view and the view resolver .
Page: {view resolver prefix} + viewName + {view resolver suffix}
@GetMapping("/add/{a}/{b}")
public String add(@PathVariable String a , @PathVariable int b, Model model) {
String res = a + b;
model.addAttribute("msg","结果为：" + res);
return "hello"; // 视图名称
}
<!-- 视图解析器 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"
id="internalResourceViewResolver">
<!-- 前缀 -->
<property name="prefix" value="/WEB-INF/jsp/" />
<!-- 后缀 -->
<property name="suffix" value=".jsp" />
</bean>
2ServletAPI [not meaningful]
By setting ServletAPI, no view resolver is required.
1 Output
through HttpServletResponse 2 Redirect
through HttpServletResponse 3 Redirect through HttpServletRequest
3SpringMVC [Key Points]
Realize forwarding and redirection through SpringMVC, no view resolver is required,
provided that the view resolver is commented out
2 data processing
1 processing submitted data
1 The submitted domain name is consistent with the parameter name of the processing method
2 The submitted domain name is inconsistent with the parameter name of the processing method
3 Submitted is an object
3 data display to the front end
1 through ModelAndView
2 through ModelMap
3 through Model
Compared
Model has only a few methods that are only suitable for storing data, which simplifies the operation and understanding of Model objects by novices;
ModelMap inherits LinkedMap, in addition to implementing some of its own methods, it also inherits the methods and characteristics of LinkedMap;
ModelAndView can be stored in At the same time of data, you can set the return logic view and control the jump of the display layer.
4 Garbled problem
index.jps
<%--
Created by IntelliJ IDEA.
User: DELL
Date: 2021/1/24
Time: 14:30
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>$Title$</title>
</head>
<body>
<form action="/e/t" method="post">
<input type="text" name="name">
<input type="submit">
</form>
</body>
</html>
Encoding.java
package com.zs.controller;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
@Controller
public class Encoding {
@PostMapping("/e/t")
public String test(@RequestParam("name") String name , Model model) {
model.addAttribute("msg",name);
return "hello";
}
}
In the test, the
garbled problem was solved by a filter, but SpringMVC provides us with a filter, which can be configured in web.xml
to solve the garbled code. Generally this kind of spring can solve it.
<filter>
<filter-name>encoding</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>utf-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
Final solution
<!-- 配置过滤器-->
<filter>
<filter-name>encoding</filter-name>
<filter-class>com.zs.controller.GenericEncodingFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
package com.zs.controller;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.Map;
/**
* 解决get和post请求 全部乱码的过滤器
*/
public class GenericEncodingFilter implements Filter {
@Override
public void destroy() {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
//处理response的字符编码
HttpServletResponse myResponse=(HttpServletResponse) response;
myResponse.setContentType("text/html;charset=UTF-8");
// 转型为与协议相关对象
HttpServletRequest httpServletRequest = (HttpServletRequest) request;
// 对request包装增强
HttpServletRequest myrequest = new MyRequest(httpServletRequest);
chain.doFilter(myrequest, response);
}
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
}
//自定义request对象，HttpServletRequest的包装类
class MyRequest extends HttpServletRequestWrapper {
private HttpServletRequest request;
//是否编码的标记
private boolean hasEncode;
//定义一个可以传入HttpServletRequest对象的构造函数，以便对其进行装饰
public MyRequest(HttpServletRequest request) {
super(request);// super必须写
this.request = request;
}
// 对需要增强方法 进行覆盖
@Override
public Map getParameterMap() {
// 先获得请求方式
String method = request.getMethod();
if (method.equalsIgnoreCase("post")) {
// post请求
try {
// 处理post乱码
request.setCharacterEncoding("utf-8");
return request.getParameterMap();
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
} else if (method.equalsIgnoreCase("get")) {
// get请求
Map<String, String[]> parameterMap = request.getParameterMap();
if (!hasEncode) {
// 确保get手动编码逻辑只运行一次
for (String parameterName : parameterMap.keySet()) {
String[] values = parameterMap.get(parameterName);
if (values != null) {
for (int i = 0; i < values.length; i++) {
try {
// 处理get乱码
values[i] = new String(values[i]
.getBytes("ISO-8859-1"), "utf-8");
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
}
}
hasEncode = true;
}
return parameterMap;
}
return super.getParameterMap();
}
//取一个值
@Override
public String getParameter(String name) {
Map<String, String[]> parameterMap = getParameterMap();
String[] values = parameterMap.get(name);
if (values == null) {
return null;
}
return values[0]; // 取回参数的第一个值
}
//取所有值
@Override
public String[] getParameterValues(String name) {
Map<String, String[]> parameterMap = getParameterMap();
String[] values = parameterMap.get(name);
return values;
}
}