解决ajax请求(SpringMVC后台)响应415/400/405错误

后端代码

• bean

  
  
   public class user {
  
       private String username;
  
       private String password;
  
       private Integer age;
  
   //省略get set
  
  }
  

• SpringMVC

  
  
     	@RequestMapping(value = "testMethod",method = RequestMethod.POST)
  
       @ResponseBody
  
      public String getUser(@RequestBody user u){
  
          System.out.println(u);
  
              return "success";
  
      }
  
  

415错误

没有设置 contentType: "application/json"

• ajax

  $.ajax({
  
      url:baseurl+"test/testMethod",
  
       type:"POST",
  
      data:JSON.stringify({
  
          "username":"user666",
  
          "password":"a123456",
  
          "age":19
  
      }),
  
      success:function (res) {
  
          console.log(res);
  
      },
  
          error:function () {
  
          console.log("网络错误");
  
          }
  
      })
  

• 原因

  
  
  //没有设置contentType: "application/json",
  
  //更正之后
  
  $.ajax({
  
      url:baseurl+"test/testMethod",
  
      type:"POST",
  
  	contentType: "application/json",
  
      data:JSON.stringify({
  
          "username":"user666",
  
          "password":"a123456",
  
          "age":19
  
      }),
  
      success:function (res) {
  
          console.log(res);
  
      },
  
      error:function () {
  
          console.log("网络错误");
  
      }
  
  })
  
  

400错误

没有对传输的内容进行格式化 JSON.stringify(jsonobj)

• ajax

  
  
  $.ajax({
  
      url:baseurl+"test/testMethod",
  
      type:"POST",
  
  	contentType: "application/json",
  
      data:{
  
          "username":"user666",
  
          "password":"a123456",
  
          "age":19
  
      },
  
      success:function (res) {
  
          console.log(res);
  
      },
  
      error:function () {
  
          console.log("网络错误");
  
      }
  
  })
  

• 原因

  
  
  //没有对传输的数据进行转换为JSON字符串JSON.stringify(jsonobj)
  
  //更正之后
  
  $.ajax({
  
      url:baseurl+"test/testMethod",
  
      type:"POST",
  
  	contentType: "application/json",
  
      data:JSON.stringify({
  
          "username":"user666",
  
          "password":"a123456",
  
          "age":19
  
      }),
  
      success:function (res) {
  
          console.log(res);
  
      },
  
      error:function () {
  
          console.log("网络错误");
  
      }
  
  })
  

405错误

通常是type 请求类型设置与后端所限制的请求不一致

• ajax

  
  
  $.ajax({
  
      url:baseurl+"test/testMethod",
  
      type:"GET",
  
  	contentType: "application/json",
  
      data:JSON.stringify({
  
          "username":"user666",
  
          "password":"a123456",
  
          "age":19
  
      }),
  
      success:function (res) {
  
          console.log(res);
  
      },
  
      error:function () {
  
          console.log("网络错误");
  
      }
  
      })
  
  

• 原因

  
  
  //请求类型与后端设置的不一致 正确应为 type:"POST"
  
  //更正之后
  
  $.ajax({
  
      url:baseurl+"test/testMethod",
  
      type:"POST",
  
  	contentType: "application/json",
  
      data:JSON.stringify({
  
          "username":"user666",
  
          "password":"a123456",
  
          "age":19
  
      }),
  
      success:function (res) {
  
          console.log(res);
  
      },
  
      error:function () {
  
          console.log("网络错误");
  
      }
  
  })