网上淘到的很帅的自适应的iframe代码

<! DOCTYPEhtmlPUBLIC"-//W3C//DTDXHTML1.0Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd" >
< html xmlns ="http://www.w3.org/1999/xhtml" >
< head >
< title ></ title >
</ head >
< body >
< iframe src ="x.htm" name ="content" id ="content" allowtransparency ="true" align ="default" marginwidth ="0" marginheight ="0" frameborder ="0" scrolling ="no" height ="200" width ="780" onload ="this.height=0;varfdh=(this.Document?this.Document.body.scrollHeight:this.contentDocument.body.offsetHeight);this.height=(fdh&gt;200?fdh:200)" > Thismessageisonlyvisibletoolderbrowsers. </ iframe >
</ body >
</ html >