<script type="text/javascript">function addOnBeforeUnload(e) { var ev = e || event; ev && (ev.returnValue = ‘你确定要离开？‘);}if(window.attachEvent){ window.attachEvent(‘onbeforeunload‘, addOnBeforeUnload);} else { window.addEventListener(‘beforeunload‘, addOnBeforeUnload, false);}</script>原文：http://www.cnblogs.com/loweringye/p/5667831.html