关于ifream的页面镶嵌高度调节

<iframe
   id="frame_content"
   src="test.html"
   scrolling="no"
   frameborder="0" width="100%" onload="this.height=this.contentWindow.document.documentElement.scrollHeight">
 </iframe>

function changeFrameHeight() {
    var ifm = document.getElementById("frame_content");
    ifm.height = document.documentElement.clientHeight - 100;
}

window.onresize = function () {
    changeFrameHeight()
}