如果不跨域的话直接通过dom对象去访问就行了。
<html>
<head>
<title></title>
</head>
<body>
<iframe src="javascript:document.write('Hello World!')" name=iframe1></iframe>
<SCRIPT LANGUAGE="JavaScript" defer>
<!--
alert(iframe1.document.body.innerHTML)
//-->
</SCRIPT>
</body>
</html>如果跨了域,出于安全性考虑,浏览器禁止了的。除非写hta并且允许了iframe的application属性
<iframe application="yes" src="http://www.csdn.net">...
<html>
<head>
<title></title>
</head>
<body>
<iframe src="javascript:document.write('Hello World!')" name=iframe1></iframe>
<SCRIPT LANGUAGE="JavaScript" defer>
<!--
alert(iframe1.document.body.innerHTML)
//-->
</SCRIPT>
</body>
</html>如果跨了域,出于安全性考虑,浏览器禁止了的。除非写hta并且允许了iframe的application属性
<iframe application="yes" src="http://www.csdn.net">...
<head>
<title></title>
</head>
<body>
<iframe src="javascript:document.write('<iframe name=iframe2 src="javascript:document.write(123)"></iframe>')" name=iframe1></iframe>
<SCRIPT LANGUAGE="JavaScript" defer>
<!--
alert(iframe1.iframe2.document.body.innerHTML)
//-->
</SCRIPT>
</body>
</html>
<html>
<body>
<!-- <iframe src="javascript:document.write("<iframe name=iframe2 src=\"javascript:document.write('<iframe name=iframe3 src=\\\'javascript:document.write(123)\\\'></iframe>')\"></iframe>")" name=iframe1></iframe> -->
<iframe src="javascript:document.write("<iframe name=iframe2 src=\"javascript:document.write(&quot;<iframe name=iframe3 src=\\\&quot;javascript:document.write(&amp;quot;<iframe name=iframe4 src=\\\\\&amp;quot;javascript:document.write(\\\\\\\&amp;amp;quot;Hello World !\\\\\\\&amp;amp;quot;)\\\\\&amp;quot;></iframe>&amp;quot;)\\\&quot;></iframe>&quot;)\"></iframe>")" name=iframe1></iframe>
<SCRIPT LANGUAGE="JavaScript" defer>
<!--
alert(iframe1.iframe2.iframe3.iframe4.document.body.innerHTML)
//-->
</SCRIPT>
</body>
</html>