#divTips{
            filter:alpha(opacity=30); /*IE滤镜，透明度50%*/
            -moz-opacity:0.3; /*Firefox私有，透明度50%*/
            opacity:0.3;/*其他，透明度50%*/
            position: absolute;width: 600px; height: 400px;display:none;color:red;z-index:10;padding:10px;
        }
   
   
        $(function () {
            var $txtNote = $("#txtNote");
            var $divTips = $("#divTips");
            $txtNote.focus(function () {
                //置焦点时隐藏
                $divTips.hide();
            }).blur(function () {
                //离开时， 如果为空则显示，否则隐藏. 然后定位
                $divTips.toggle($txtNote.val() == "")
                    .css({
                        "left": $txtNote.position().left,
                        "top" : $txtNote.position().top
                    });
            });
            $divTips.click(function () {
                $txtNote.focus();
            });
            $txtNote.blur();
        });
   


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