What is the best way to check if Ajax call is 200 OK if I'm returning the table?

Question

I have a question about ajax success. So in previous situations I have returned Data something like ID but now in this case I'm returning entire table. So I would like to check if Ajax was successful(200 OK) before I retrieve my data. What is the best way to do that? Also I use new way to retrieve data and check for errors with JQuery. Here is example of my code:

<div id="box"></div>

function getSlots(fld){
    var userID = '134';

    $j.ajax({
        type:  'POST',
        url:  'AjaxData.html',
        cache:  false,
        data:  {'userID':userID},
            dataType: "html",
            async:   false
        })  
        .done(function(html){
            $j('#box').html(html);
        })
        .fail(function(jqXHR, textStatus, errorThrown){ 
            gwLogIt(errorThrown);
        }); 
    }

Why do you need to check for `200 OK`? Doesn't `.done` check for that for you? What problem are you facing with this code? — gen_Eric, Apr 29 '16 at 19:06
P.S. Why are you using `async: false`? I wouldn't suggest using that because it will lock up the user's browser until the call is done. — gen_Eric, Apr 29 '16 at 19:07
I do not know if .done actually check for that. In the past I was putting if statement inside of success. — espresso_coffee, Apr 29 '16 at 19:07
Nothing, remove that line. Why are you using it? AJAX is supposed to be *asynchronous*. — gen_Eric, Apr 29 '16 at 19:15
I think that I used on one of my previous pages and I haven't removed. Thanks. — espresso_coffee, Apr 29 '16 at 19:16

score 4 · Answer 1 · answered Apr 29 '16 at 19:13

You don't need to check. The various callbacks are called under the following conditions:

.done() or success: are called when the AJAX call is successful.
.fail() or error: are called when there's an error (either from the server or in the jQuery code that parses the response).
.always() or complete: are called in either case.

score 2 · Answer 2 · answered Apr 29 '16 at 19:09

from official docs:

$.ajax({
  statusCode: {
    404: function() {
      alert( "page not found" );
    }
  }
});

http://api.jquery.com/jQuery.ajax/

also if you use something like babel to transpile ES6, you can use fetch api for ajax calls. I personally stopped using jQuery ±2 years ago.. when moved to React world :)

What is the best way to check if Ajax call is 200 OK if I'm returning the table?

2 Answers2