iframe自适应高度

<iframe id="frame_content" src="iframe_b.html" scrolling="no" frameborder="0"></iframe><script type="text/javascript">

function reinitIframe(){

var iframe = document.getElementById("frame_content");

try{

iframe.height = iframe.contentWindow.document.documentElement.scrollHeight;

}catch (ex){}

}

window.setInterval("reinitIframe()", 200);