jQuery get response from ajax function

Question

I have written a function which is used when a form is posted to post data to a URL. However I'm not sure how I can return the result within the function so that I can check when the function is called, what the response is.

Basically I want the response value in the function to be returned so that I can access it.

/**
 * Submit (POST) the Form via Ajax
 *
 * @param form
 * @param action
 * @param data
 * @param container
 */
function postForm(form,action,method,container){
    $.ajax({
        type: 'post',
        dataType: 'json',
        url: action,
        data: form.serialize(),
        error: function(xhr, status, error) {
            // Display errors
            var err = JSON.parse(xhr.responseText);
            var errMsg = '';
            $.each(err, function(name, val) {
                errMsg += val + '<br>';
            });

            new PNotify({
                title: "Error!",
                text: errMsg,
                type: 'error',
                animate_speed: 'fast'
            });
        },
        success: function (response) {
            handleResponse(method, container, response);
            return response;
        }
    });
}

I want to use it like this:

var result = postForm(
    form, 
    form.attr('action'),
    form.attr('data-method'),
    $(form.attr('data-container'))
);
alert(result);

At the moment, the var result outputs undefined.

Please help!

`$.ajax` is asynchronous. It might take a while to get a response. — Moob, Nov 26 '15 at 15:49
you need to return a promise from your PostForm function. you have to understand this concept before you move on: https://api.jquery.com/promise/ — Avi, Nov 26 '15 at 15:57

score 1 · Accepted Answer · edited May 23 '17 at 12:30

Your function should return a promise object:

function postForm(form,action,method,container){
    var promise = $.ajax({
        type: 'post',
        dataType: 'json',
        url: action,
        data: form.serialize(),
        error: function(xhr, status, error) {
            // Display errors
            var err = JSON.parse(xhr.responseText);
            var errMsg = '';
            $.each(err, function(name, val) {
                errMsg += val + '<br>';
            });

            new PNotify({
                title: "Error!",
                text: errMsg,
                type: 'error',
                animate_speed: 'fast'
            });
        },
        success: function (response) {
            handleResponse(method, container, response);
            return response;
        }
    });
         return promise;   
}

now your caller will reference the promise of the ajax request. so now you do:

var promise = PostForm(...);
promise.done(function(data) {
    do your thing
  })

You should read this:How do I return the response from an asynchronous call?

score 0 · Answer 2 · answered Nov 26 '15 at 15:57

You can handle the situation like this:

success: function (response) {
    handleResponse(method, container, response);
    //return response;
    doSomething(response);
}

and then:

function doSomething(response) {
    alert(response);
}

maybe you want to make the call sync (not suggested) by specifying:

$.ajax({
        type: 'post',
        dataType: 'json',
        url: action,
        async: false
        ...

jQuery get response from ajax function

2 Answers2