Phantom JS加载更多元素

I need to scrap Facebook video page but the "load more button" is in Ajax. So I try to use PhantomJS to click on the button.

But, I need to click many times on the button.

So this is my code :

var page = require('webpage').create();

page.open("https://www.facebook.com/MisterVOnline/videos", function(status) {
    if ( status === "success" ) {
        page.evaluate(function() {
            while(document.querySelector(".uiMorePagerPrimary")){
                document.querySelector(".uiMorePagerPrimary").click();
                window.setTimeout(function () {
                }, 5000);
            }
        });
        window.setTimeout(function () {
            //console.log(page.content);
            page.render('facebook.jpeg');
            phantom.exit();
        }, 5000);
    }
});

The code does not work when without the while loop, he made ​​a good load...

I hope that someone could help me !

Problem solved : use setInterval instead while loop :

var myTime = setInterval(function(){
    if(document.querySelector(".uiMorePagerPrimary")!=null)
    {
        nbTry=0;
        document.querySelector(".uiMorePagerPrimary").click();
    }
    else 
    {
        nbTry++;
    }
    if(nbTry>5)
    {
        clearInterval(myTime);
        window.callPhantom({ exit: true });
    }
}, 500);