js访问iframe里面DOM
解决一个让iframe的高度自适应src文件的高度，提供两种解决方法：
main.html
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>main</title>
<script>
//方法1
var iframe_inner = function( h ){
document.getElementById('frame').height = h;
alert("方法1---" + h);
}
//方法2
window.onload = function(){
var iObj = document.getElementById('frame');
var height = iObj.contentWindow.document.documentElement.scrollHeight;
iObj.height = height;
alert("方法2---" + height);
};
</script>
</head>
<body>
<iframe src="src.html" id="frame" />
</body>
</html>
src.html
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>src</title>
<script>
window.onload = function(){
parent.iframe_inner(document.documentElement.scrollHeight);
}
</script>
</head>
<body style="height:300px;">
</body>
</html>