How to get response status code from jQuery.ajax?_问答_开发者

In the following code, all I am trying to do is to get the HTTP response code from a jQuery.ajax call. Then, if the code is 301 (Moved Permanently), display the 'Location' response header:

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
   "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
  <title>jQuery 301 Trial</title>
  <script src="http://code.jquery.com/jquery-1.5.1.min.js"></script>

  <script type="text/javascript">
  function get_resp_status(url) {
    $.ajax({
      url: url,
      complete: function (jqxhr, txt_status) {
        console.log ("Complete: [ " + txt_status + " ] " + jqxhr);
        // if (response code is 301) {
        console.log ("Location: " + jqxhr.getResponseHeader("Location"));
        // }
      }
    });
  }
  </script>
  <script type="text/javascript">
  $(document).ready(function(){
    $('a').mouseenter(
      function () {
        get_resp_status(this.href);
      },
      function () {
      }
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  });
  </script>
</head>
<body>
  <a href="http://ow.ly/4etPl">Test 301 redirect</a>
  <a href="http://cnn.com/not_found">Test 404 not found</a>
</body>
</html>

Can someone point out where I am going wrong? When I check the 'jqxhr' object in Firebug, I can't find the status code, nor the 'Location' response header. I set the breakpoint on last line of 'complete'.

Thanks much.

I see the status field on the jqXhr object, here is a fiddle with it working:

http://jsfiddle.net/magicaj/55HQq/3/

$.ajax({
    //...        
    success: function(data, textStatus, xhr) {
        console.log(xhr.status);
    },
    complete: function(xhr, textStatus) {
        console.log(xhr.status);
    } 
});

Came across this old thread searching for a similar solution myself and found the accepted answer to be using .complete() method of jquery ajax. I quote the notice on jquery website here:

The jqXHR.success(), jqXHR.error(), and jqXHR.complete() callbacks are deprecated as of jQuery 1.8. To prepare your code for their eventual removal, use jqXHR.done(), jqXHR.fail(), and jqXHR.always() instead.

To know the status code of a ajax response, one can use the following code:

$.ajax( url [, settings ] )
.always(function (jqXHR) {
    console.log(jqXHR.status);
});

Works similarily for .done() and .fail()

It is probably more idiomatic jQuery to use the statusCode property of the parameter object passed to the the $.ajax function:

$.ajax({
  statusCode: {
    500: function(xhr) {
      if(window.console) console.log(xhr.responseText);
    }
  }
});

However, as Livingston Samuel said, it is not possible to catch 301 status codes in javascript.

When your XHR request returns a Redirect response (HTTP Status 301, 302, 303, 307), the XMLHttpRequest automatically follows the redirected URL and returns the status code of that URL.

You can get the non-redirecting status codes (200, 400, 500 etc) via the status property of the xhr object.

So you cannot get the redirected location from the response header of a 301, 302, 303 or 307 request.

You might have to change your server logic to respond in a way that you can handle the redirect, rather than letting the browser do it. An example implementation.

You can check your respone content, just console.log it and you will see whitch property have a status code. If you do not understand jsons, please refer to the video: https://www.youtube.com/watch?v=Bv_5Zv5c-Ts

It explains very basic knowledge that let you feel more comfortable with javascript.

You can do it with shorter version of ajax request, please see code above:

$.get("example.url.com", function(data) {
                console.log(data);
            }).done(function() {
               // TO DO ON DONE
            }).fail(function(data, textStatus, xhr) {
                 //This shows status code eg. 403
                 console.log("error", data.status);
                 //This shows status message eg. Forbidden
                 console.log("STATUS: "+xhr);
            }).always(function() {
                 //TO-DO after fail/done request.
                 console.log("ended");
            });

Example console output:

error 403 
STATUS: Forbidden 
ended

NB: Using jQuery 3.4.1

$.ajax({
  url: URL,
  success: function(data, textStatus, jqXHR){
    console.log(textStatus + ": " + jqXHR.status);
    // do something with data
  },
  error: function(jqXHR, textStatus, errorThrown){
    console.log(textStatus + ": " + jqXHR.status + " " + errorThrown);
  }
});

jqxhr is a json object:

complete returns:
The jqXHR (in jQuery 1.4.x, XMLHTTPRequest) object and a string categorizing the status of the request ("success", "notmodified", "error", "timeout", "abort", or "parsererror").

see: jQuery ajax

so you would do:

jqxhr.status to get the status