angular.js - $http callback function and return code issues

Question

{Code...} $http.jsonp(url) {Code...} When there is no data in the database, the console network information shows that the status is 200 response return data console.log(res) printed information Why is the network displayed there? The status is 200, but when printed it becomes 404, no...

滿天的星座 · Answer

The URL address needs to add ?callback=JSON_CALLBACK. The result of your Response is: ({"returnCode": "-1"})。正常Response的结果是：/**/angular.callbacks._0({"found":12,"posts": []});
The following is an online example: angularjs-http-jsonp-service-example. Remove the callback query parameter and take a look at the result.

Why the status displayed by the developer tools is 200? It just means that the HTTP request is successful. Why is 404 returned?

if (event) {
  // JS成功加载但回调未被调用
  if (event.type === 'load' && 
    !callbacks.wasCalled(callbackPath)) {
          event = { type: 'error' };
        }
        text = event.type;
        status = event.type === 'error' ? 404 : 200;
  }
}

Please refer to the AngularJS httpBackend source code for details.

jsonpReq only ever sets status to 200 (OK), 404 (ERROR) or -1 (WAITING) - httpBackend.js#65