Source
<HTML>
<BODY>
<FORM>

<INPUT Type=Button Value="開啟空白視窗(win1)" OnClick="win1=window.open('');"><P>
<INPUT Type=Button Value="開啟 x.htm (win2)" OnClick="win2=window.open('x.htm');"><P>
<HR WIDTH="100%">
<INPUT Type=Button Value="關閉 win1" OnClick=" win1.close();"><P>
<INPUT Type=Button Value="關閉 win2" OnClick="win2.close();"><P>

</FORM>

</BODY>
</HTML>