jq放大镜

JQ放大镜

*{
padding: 0;
margin: 0;
}
.outer{
width: 200px;
margin: 80px auto;
position: relative;
}
.big{
width: 180px;
height: 180px;
position: absolute;
border-radius: 100%;
box-shadow: 0 0 0 7px rgba(255,255,255,0.8),0 0 7px 7px rgba(0,0,0,0.3),inset 0 0 40px 2px rgba(0,0,0,0.3);
background: url(iphone.jpg) no-repeat;
display: none;
}
.small{
display: block;
}

<script type="text/javascript" src="../jquery-1.8.3.min.js"></script><script type="text/javascript">    $(function(){        // 定义实际图片的大小        var imgWidth = 0;        var imgHeight = 0;        $(".small").load(function(){            // 创建图片对象            var imgObj = new Image();            imgObj.src = $(this).attr("src");            imgWidth =imgObj.width;            imgHeight = imgObj.height;            $(".outer").mousemove(function(e){                var outerOffset = $(this).offset();                var mx = e.clientX - outerOffset.left;                var my = e.clientY - outerOffset.top;                // 放大镜的显示与隐藏                if(mx > 0 && mx < $(this).width() && my > 0 && my < $(this).height()){                    $(".big").fadeIn(100);                }else{                    $(".big").fadeOut(100);                }                // 判断放大镜可显示                if($(".big").is(":visible")){                    var rx = Math.round(mx/$(".small").width()*imgWidth - $(".big").width()/2)*-1;                    var ry = Math.round(my/$(".small").height()*imgHeight - $(".big").height()/2)*-1;                    var bgp = rx + "px " + ry + "px";                    // 放大镜跟随鼠标                    var gx = mx - $(".big").width()/2;                    var gy = my - $(".big").height()/2;                    $(".big").css({                        left:gx,                        top:gy,                        backgroundPosition:bgp,                    })                }            })        })    })</script>