一个父窗口，能否做到当此父窗口被关闭时，调用onunload方法来关闭所有从此父窗口打开的子窗口
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1<body onunload="if(s1!=null) s1.close();">
2<input onclick="aa()" type="button"/>
3<script>
4var s1 = null;
5function aa(){
6s1 = window.open("3.htm");
7}
8</script>
9\---------------------------------------------------------------
10
11s1 = window.open("3.htm");返回句柄,可以对si进行操作
12\---------------------------------------------------------------
13
14通过opener.close()或通过弹出窗口的句柄.close();
15\---------------------------------------------------------------
16
17把打开的窗口记到一个数组里</body>