<div><a id="a1" onmouseover="javascript:show('a1','div1');" onmouseout="hide('div1')">鼠标放上去1</a></div>

<div id="div1" onmouseover="javascript:show('a1','div1');" onmouseout="hide('div1')" style="display: none; width: 218px; font-size: 12px; color: #333; border: 1px solid #FF6600; border-top: none; margin: 0px; background-color: #fff; position: absolute">

    <ul>

        <li><a href="#">运动</a></li>

        <li><a href="#">钟表</a></li>

        <li><a href="#">男装</a></li>

        <li><a href="#">钻石饰品</a></li>

        <li><a href="#">女装</a></li>

        <li><a href="#">金银投资</a></li>

    </ul>

</div>

<script>

    var ishide = 0;//判断是否需要隐藏div

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        var obj1 = $("#" + id1 + "");

        var obj2 = $("#" + id2 + "");

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        $(obj2).css("display", "block");

        //var X = obj1.offset().top;

        //var Y = obj1.offset().left;

        //$(obj2).offset({ top: X + 20, left: Y })

        //$(obj2).css("left", X);

        //$(obj2).css("top", Y + 10);

    }

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        setTimeout(hide2, 400, id2);

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            $(obj2).css("display", "none");

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</script>