<html>
<body>
<iframe id="qinyuanIframe" src="login.html" ></iframe>
<a href="javascript:;" onclick="getIframeContent('qinyuanIframe');">Get the content of Iframe</a>
</body>
<script>
//iframe獲取內容需要注意的一點是:"#qinyuanIframe"的src是在不存在跨域的前提條件下，不然存在"VM475:3 Uncaught DOMException: Blocked a frame with origin "http://192.168.10.6:9999" from accessing a cross-origin frame.
at getIframeContent (<anonymous>:3:44)
at <anonymous>:5:3"
function getIframeContent(frameId){
var frameObj = document.getElementById(frameId);
var frameContent = frameObj.contentWindow.document.body.innerHTML;
alert("frame content : "+frameContent);
}
</script>
</html>