Spring MVC 获取不到 ajaxs 参数值

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<script type="text/javaScript" src="${pageContext.request.contextPath }/js/jquery-3.6.0.min.js">
</script>
<body>

<form name="Form2"  id="form2" action ="" method="post"  enctype="multipart/form-data"> 
 姓名:<input type="text" name="name" id="name">
 密码:<input type="text" name="password" id="password">
 <input type="button" value="测试" onclick="testJson()" />
</form> 

</body>
<script type="text/javascript">
function testJson() {
    alert("进来了");
    var name = $("#name").val();
    var password = $("#password").val();
    alert("姓名"+name+",学校:"+password);
    $.ajax({
        //请求路径
        url : "fileupload",
        //请求类型
        type : "post",
        //data表示发送的数据
        data :{
                "name" : name,
                "password" : password
            }, //定义发送请求的数据格式为JSON字符串
        contentType : "application/json;charset=utf-8",
        //定义回调响应的数据格式为JSON字符串，该属性可以省略
        dataType : "json",
        //成功响应的结果
        success : function(data) {
            alert(data);
            if (data != null) {
                alert("输入的用户名：" + data.name + "，密码：" + data.password);
            }
        }
    });
}  
 

</script>

</html>

上面是jsp页面

controller方法

package com.zjf.controller;

import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.view.json.MappingJackson2JsonView;

@Controller
public class FileUpLoad {

    @RequestMapping("/fileupload")
    public ModelAndView fileupload(HttpServletRequest request,HttpServletResponse rs) {
        String name = request.getParameter("name");
        String password = request.getParameter("password");
        System.out.println("name:"+name+",password:"+password);
        Map<String, String> map = new HashMap<>();
        map.put("name", name+"1");
        map.put("password", password+"1");
        return new ModelAndView(new MappingJackson2JsonView(), map);
    }
}

调用的时候 request.getParameter("name");获取的值一直是null;

调试N次最后发现是 contentType 的问题。真是无语！去掉 contentType 就可以获取到 data值了

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="ISO-8859-1">
<title>Insert title here</title>
</head>
<script type="text/javaScript" src="${pageContext.request.contextPath }/js/jquery-3.6.0.min.js">
</script>
<body>

<form name="Form2"  id="form2" action ="" method="post"  enctype="multipart/form-data"> 
 姓名:<input type="text" name="name" id="name">
 密码:<input type="text" name="password" id="password">
 <!-- 上传人:<input type="text" name="name">
 上传名:<input type="text" name="fileName"> -->
 <input type="button" value="测试" onclick="testJson()" />
</form> 

</body>
<script type="text/javascript">
function testJson() {
    alert("进来了");
    var name = $("#name").val();
    var password = $("#password").val();
    alert("姓名"+name+",学校:"+password);
    $.ajax({
        //请求路径
        url : "fileupload",
        //请求类型
        type : "post",
        //data表示发送的数据
        data :{
                "name" : name,
                "password" : password
            }, 
        //定义回调响应的数据格式为JSON字符串，该属性可以省略
        dataType : "json",
        //成功响应的结果
        success : function(data) {
            alert(data);
            if (data != null) {
                alert("输入的用户名：" + data.name + "，密码：" + data.password);
            }
        }
    });
}  
 

</script>

</html>