FB.Canvas.getPageInfo no return in callback function

 function getpageinfo()
{
alert('start');
FB.Canvas.getPageInfo(
    function(info) {
  alert('got');
        alert('Width: ' + info.clientWidth + ' Height: ' + info.clientHeight);
    }
alert('end');
开发者_运维百科}

i have loaded facebook javascript jdk, also have ,and FB.init() before call this function ,

but when call the function there only have two alert "start" and "end" , i never got the alert "got" , seems the FB.Canvas.getPageInfo's callback function never worked .

does the FB.Canvas.getPageInfo really can work ? or can someone give me a url which used this method and workd ? very thanks .

Your FB.Canvas.getPageInfo( doesn't have a closing bracket.