javascript关闭IE不弹出对话框

<script type="text/javascript">function closeWindow(){var ua = navigator.userAgent.toLowerCase(); if(ua.indexOf('MSIE 5.0')!=-1||ua.indexOf('MSIE 6.0')!=-1){ window.opener=null; window.close();}else {window.opener=null;window.open('','_top');window.close();}}</script>

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