设置ifrme子页面的滚动条滚动至某元素位置

function srollToCatalog(id,pid){
   var iframe=document.getElementById('iframe'+pid);
   var iframeDocument = iframe.contentWindow.document;
   var element = iframeDocument.getElementById(id);
   $(iframeDocument.documentElement).animate({scrollTop:$(element)[0].offsetTop},300);//136
}