Solution to Ajax request being sent successfully but not succeeding (picture and text tutorial)

Now I will share with you a solution to the problem that the Ajax request is sent successfully but does not enter the success. It has a good reference value and I hope it will be helpful to everyone.

1. Situation description: ajax was sent successfully, the background also successfully responded to the request, and returned json data. You can also see the response json by monitoring the request through chrome The data, but does not enter the success method, instead goes to the error method

Front end:

$.ajax({
 type : "get",
 data : {'dbId':node.dbId,'viewId':node.id,'date':new Date()},
 url : "${ctp}/ViewOperate/ShowViewSql",
 dataType : "json",
 success : function(data){
   console.log(data);
   layer.alert(data,{
     skin: 'layui-layer-molv'
   });
 }
 error : function(data){
   layer.alert("进入了error方法",{
     skin: 'layui-layer-molv'
   });
 }
});

Backend:

@RequestMapping(value="/ShowViewSql",method=RequestMethod.GET)
@ResponseBody
public String showCreateViewSql(@RequestParam(value="dbId",required=false)Integer dbId,
   @RequestParam(value="viewId",required=false)Integer viewId) {
 return "abc";
}

Reason: When the json data returned by the background is a pure String type object, after the front-end dataType attribute is set to json, it will be considered that the json data format converted from the String object is not a standard json format, so the method corresponding to the error will be executed. .

Solution: No need to change the backend, just set the dataType attribute in the front-end ajax request to text

$.ajax({
   type : "get",
   data : {'dbId':node.dbId,'viewId':node.id,'date':new Date()},
   url : "${ctp}/ViewOperate/ShowViewSql",
   dataType : "text",
   success : function(data){
     console.log(data);
     layer.alert(data,{
       skin: 'layui-layer-molv'
     });
   }
   error : function(data){
     layer.alert("进入了error方法",{
       skin: 'layui-layer-molv'
     });
   }
});

Special cases: When the json number returned by the backend is similar to "1", "2", "22", "232123", " -1", "232123.44" numeric string, when the front-end dataType attribute is set to json, the success method can be entered normally. The reason is unknown.

The above is what I compiled for everyone. I hope it will be helpful to everyone in the future.

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MUi framework ajax request WebService interface example_AJAX related

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