javascript 能不能改变frame 的大小

demo.htm<frameset rows="30%,40%,30%" id="baobao">
  <frame src="top.htm" name="topFrame">
  <frame src="middle.htm" name="middleFrame">
  <frame src="bottom.htm" name="bottomFrame">
</frameset>top.htm
topmiddle.htm
<input type=button onclick="window.parent.baobao.rows='0,100%,0'" value="隐藏">
<input type=button onclick="window.parent.baobao.rows='30%,40%,30%'" value="显示">bottom.htm
bottom

解决方案 »

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可我的框是这样分的
<iframe src="/index_top.jsp" trusted="yes" application="no" id="index_top" width="800" height="50" frameborder=0 scrolling=no></iframe>
<iframe src="/index_main.jsp" trusted="yes" application="no" id="index_main" width="800" height="521" frameborder=0 scrolling=no></iframe>
<iframe src="/index_bottom.jsp" trusted="yes" application="no" id="index_bottom" width="800" height="29" frameborder=0 scrolling=no></iframe>
<html><head>
<title>新建网页 1</title>
<script>
function aa()
{
document.all.iframe1.width=200;
document.all.iframe1.height=300;
}
</script>
</head><body>
<iframe href="" name="iframe1"></iframe>
<input type="button" name="B1" value="按钮" onclick="aa()">
</body></html>
demo.htm<iframe src="index_top.htm" trusted="yes" application="no" id="index_top" width="800" height="50" ></iframe>
<iframe src="index_main.htm" trusted="yes" application="no" id="index_main" width="800" height="521"></iframe>
<iframe src="index_bottom.htm" trusted="yes" application="no" id="index_bottom" width="800" height="29"></iframe>
index_top.htm
topindex_main.htm<input type=button onclick="Hidden()" value="隐藏">
<input type=button onclick="Show()" value="显示"><script>
function Show()
{
    top.document.all["index_top"].style.height="50";
    top.document.all["index_main"].style.height="521";
    top.document.all["index_bottom"].style.height="29";
}
function Hidden()
{
    top.document.all["index_top"].style.height="0";
    top.document.all["index_main"].style.height="600";
    top.document.all["index_bottom"].style.height="0";
}
</script>index_bottom.htm
bottom
请教一下，top.document.all..中的top是什么对象指令？它是指什么的？应该看什么参考资料才有相关的材料？恳请赐教，谢谢。
顶层窗口对象
MSDN的library
top是指向框架的顶层.资料
HTML
http://vip.5d.cn/friday/upload/dhtml html&css.chm