Run an Ajax request on a URL blocked for detecting Adblocker (Ghostery)

I need some simple code for detecting a blocked url.

SethWhite has said: You could also try to run an ajax request on a URL blocked by an adblocker. If it succeeds, there's no adblocker, if it fails, there's an adblocker.

I can use microajax to do this in the following way:

microAjax("/resource/url", function (res) {
  alert (res);
});

How I can call window.open if the request does not succeed?

For microAjax, look up its documentation. I'd imagine in the response you can find the response code. If the code is 200 it's a success, and you can run window.open(). Otherwise, the request is likely being blocked.

var request = new XMLHttpRequest();
request.onreadystatechange = function() {
    if(request.readyState === 4 && request.status === 200 ) {
        console.log('No blocker');
    }
    else if(request.readyState === 4 && request.status === 0){
        console.log('Blocker exists');
    }
};

request.open("GET","pathTo/ads.html");
request.send();

This uses a local URL; I initially thought using external URLs was a good idea, but if they're made invalid by their owners you'll get false positives.

I tested this using Adblock Plus and it works. If this is a URL blocked by Ghostery, it should work as well; otherwise, you can try different URLs to see what's blocked.

You could also do this with jQuery's $.ajax function, but I gravitate towards vanilla JavaScript.