jQuery: Performing synchronous AJAX requests

Industrial picture Industrial · Jul 13, 2011 · Viewed 327.1k times · Source

I've done some jQuery in the past, but I am completely stuck on this. I know about the pros and cons of using synchronous ajax calls, but here it will be required.

The remote page is loaded (controlled with firebug), but no return is shown.

What should I do different to make my function to return properly?

function getRemote() {

    var remote;

    $.ajax({
        type: "GET",
        url: remote_url,
        async: false,
        success : function(data) {
            remote = data;
        }
    });

    return remote;

}

Answer

Dogbert picture Dogbert · Jul 13, 2011

As you're making a synchronous request, that should be

function getRemote() {
    return $.ajax({
        type: "GET",
        url: remote_url,
        async: false
    }).responseText;
}

Example - http://api.jquery.com/jQuery.ajax/#example-3

PLEASE NOTE: Setting async property to false is deprecated and in the process of being removed (link). Many browsers including Firefox and Chrome have already started to print a warning in the console if you use this:

Chrome:

Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user's experience. For more help, check https://xhr.spec.whatwg.org/.

Firefox:

Synchronous XMLHttpRequest on the main thread is deprecated because of its detrimental effects to the end user’s experience. For more help http://xhr.spec.whatwg.org/