var oFrm = document.getElementById('Iframe4'); oFrm.onload = oFrm.onreadystatechange = function () { if (this.readyState && this.readyState != 'complete') { //alert("加载中。。。"); } else { var $listSearch = $('#Iframe4').contents().find('.listSearch'); $listSearch.css("top", "30px"); } }