1.子iframe里调用父级的方法：window.parent.document.
2.父级里调用子集iframe：window.frames["iframe_text"].document.
下面是例子：
index.html
<HTML>
<HEAD>
<TITLE> Test Page </TITLE>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="prototype-1.4.0.js"></script>
<script language="javascript">
function show()
{
window.frames["iframe_text"].document.getElementById("myH1").innerHTML = "http://hi.wonsoft.cn";
}
</script>
</HEAD>
<BODY>
<iframe height="350" width="600" src="iframe_test.html" name="iframe_text"></iframe>
<form action="" method="post">
<input name="haha" id="haha" type="text" maxlength="30" value="haha" />
<br />
<textarea cols="50" rows="5" id="getAttributeMethod"></textarea>
<input type="button" onClick="show();" value="提交"/>
</form>
<h1 id="myH1">d</h1>
</BODY>
</HTML>
<HEAD>
<TITLE> Test Page </TITLE>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script src="prototype-1.4.0.js"></script>
<script language="javascript">
function show()
{
window.frames["iframe_text"].document.getElementById("myH1").innerHTML = "http://hi.wonsoft.cn";
}
</script>
</HEAD>
<BODY>
<iframe height="350" width="600" src="iframe_test.html" name="iframe_text"></iframe>
<form action="" method="post">
<input name="haha" id="haha" type="text" maxlength="30" value="haha" />
<br />
<textarea cols="50" rows="5" id="getAttributeMethod"></textarea>
<input type="button" onClick="show();" value="提交"/>
</form>
<h1 id="myH1">d</h1>
</BODY>
</HTML>
iframe_test.html
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<script language="javascript">
function show()
{
alert(window.parent.document.body.scrollTop);
window.parent.document.getElementById("myH1").innerHTML = document.getElementById("text").value//wonsoft.cn;
}
</script>
<body>
<h1 id="myH1">ha</h1>
<form action="" method="post">
<input name="abc" id="abc" type="text" maxlength="30" value="abc" />
<br />
<textarea cols="50" rows="10" id="text"></textarea>
<br />
<input type="button" value="提交" onclick="show();"/>
</form>
</body>
</html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
</head>
<script language="javascript">
function show()
{
alert(window.parent.document.body.scrollTop);
window.parent.document.getElementById("myH1").innerHTML = document.getElementById("text").value//wonsoft.cn;
}
</script>
<body>
<h1 id="myH1">ha</h1>
<form action="" method="post">
<input name="abc" id="abc" type="text" maxlength="30" value="abc" />
<br />
<textarea cols="50" rows="10" id="text"></textarea>
<br />
<input type="button" value="提交" onclick="show();"/>
</form>
</body>
</html>