js图片放大镜特效代码

 1 <script language="JavaScript">
 2 <!--
 3 var srcX = 1024; //原图长宽
 4 var srcY = 768;
 5 var bigX = 500; //原比例预览大小,可以设置成任意大小
 6 var bigY = 300;
 7 var smallX = 256; //缩略图大小,要与原大小成比例
 8 var smallY = 192;
 9 var viewX = bigX / srcX * smallX; //预览范围
10 var viewY = bigY / srcY * smallY;
11 var bl = srcX / smallX;//缩小比例
12 var border = 8; //边框
13 window.onload=function (){
14     bigbox.style.borderWidth=border;
15     bigbox.style.width=bigX+border*2;
16     bigbox.style.height=bigY+border*2;
17     smallpic.width=smallX;
18     smallpic.height=smallY;
19     view.style.width=viewX;
20     view.style.height=viewY;
21     smallbox.style.borderWidth=border;
22     if (window.event){
23         smallbox.style.width=smallpic.offsetWidth+border*2;
24         smallbox.style.height=smallpic.offsetHeight+border*2;
25     }else{
26         smallbox.style.width=smallpic.offsetWidth;
27         smallbox.style.height=smallpic.offsetHeight;
28     }
29     move(event);
30 }
31 function move(e){
32     var e = window.event?window.event:e;
33     var iebug = 0;
34     if (window.event){
35         var vX = e.offsetX - viewX/2;
36         var vY = e.offsetY - viewY/2;
37     }else{
38         var vX = e.pageX - viewX/2 - smallbox.offsetLeft - border;
39         var vY = e.pageY - viewY/2 - smallbox.offsetTop - border;
40         iebug = 2;
41     }
42     if (vX < 0) vX = 0;
43     if (vY < 0) vY = 0;
44     if (vX > smallX - viewX - iebug) vX = smallX - viewX - iebug;
45     if (vY > smallY - viewY - iebug) vY = smallY - viewY - iebug;
46     view.style.left = vX + smallbox.offsetLeft + border;
47     view.style.top = vY + smallbox.offsetTop + border;
48     bigbox.style.backgroundPosition= - vX * bl + " " + -vY * bl;
49 }
50 //-->
51 </script>
52 
53 <style type="text/css">
54 <!--
55 *{padding:0;margin:0}
56 img{display:block;}
57 #smallbox{border:1px #c33 solid;float:left;width:0;height:0;overflow:hidden}
58 #bigbox{border:1px #c33 solid;width:0px;height:0px;float:left;background:url('/upload/20071130224657571.jpg') no-repeat;}
59 #view{border:1px #ddd solid;width:0px;height:0px;position:absolute}
60 .head{text-align:center;line-height:40px;font:bold 16px/40px;color:red}
61 //-->
62 </style>
63 <div class="head">图片放大效果</div>
64 <div id="smallbox"><img id="smallpic" src="/upload/20071130224657571.jpg" border="0" onmousemove="move(event)"></div>
65 <div id="bigbox"></div>
66 <div id="view"></div>

代码最终的效果如下图:

posted @ 2014-04-24 10:38  追逐者——Eagle  阅读(250)  评论(0编辑  收藏  举报