自己写的jQuery放大镜插件效果(二)(采用只有一张图片的思路)

 1  ; (function ($) {
 2             $.fn.gysFdj = function (options) {
 3                 var defaluts = { 
 4                     cameraW: 100, //镜头宽度
 5                     cameraH: 100, //镜头高度
 6                     pointBjColor: "#000", //镜头的背景颜色
 7                     pointOpacity: 0.6, //镜头的透明度
 8                     zoomPos: 10, //放大框距离源框的位置                
 9                     zoom: 2//放大倍数
10                 };
11                 options = $.extend(defaluts, options);
12                 var obj = $(this);               
13                 obj.addClass("gysFdjOrigin");
14                 var objOriImg=$("img",obj);
15                 var objOriImgW=objOriImg.width();
16                 var objOriImgH=objOriImg.height();                
17                 var fdCount = $(".gysFdjOrigin").length;
18                 var fdAttr = "fd"; //属性变量
19                 obj.attr(fdAttr, fdCount); //添加属性
20                 var offset = obj.offset();
21                 var objLeft = offset.left; //对象left                
22                 var objTop = offset.top; //对象top
23                 var objWidth = obj.width(); //对象宽度
24                 var objHeight = obj.height(); //对象高度              
25                 //镜头相对box的活动范围
26 
27                 var cameraMaxLeft = objWidth + objLeft - options.cameraW; //最大左范围
28                 var cameraMaxTop = objHeight + objTop - options.cameraH; //最大下范围
29 
30                 var imgStr = obj.html();
31                 var html = "";
32                 html += "<div style='left:" + (objLeft + objWidth + options.zoomPos) + "px; top:" + objTop + "px;display:none; position:absolute;width:" + (options.cameraW * options.zoom) + "px;height:" + (options.cameraH* options.zoom) + "px;overflow:hidden;' class='gysFdjBox' " + fdAttr + "=" + fdCount + ">" + imgStr + "</div>";
33                 $("body").append(html);
34                 $("img", $(".gysFdjBox[" + fdAttr + "=" + fdCount + "]")).width(objWidth*options.zoom).height(objHeight*options.zoom);
35                 var objFdjcamera = null;
36                 if ($("#gysFdjcamera").length == 0) {
37                     var pointBlock = "<div id='gysFdjcamera' style='width:" + options.cameraW + "px; height:" + options.cameraH + "px; background-color:" + options.pointBjColor + ";opacity:" + options.pointOpacity + ";filter:alpha(opacity="+options.pointOpacity*100+");cursor:crosshair;position:absolute;display:none;'></div>";
38                 $("body").append(pointBlock);                
39                 }
40                 objFdjcamera = $("#gysFdjcamera");
41                 var nowLeft = 0, nowTop = 0;
42                 obj.on("mouseover", function (event) {                   
43                     objFdjcamera.show().attr(fdAttr, fdCount);                                                            
44                     $(".gysFdjBox["+fdAttr+"="+fdCount+"]").show();
45                     $(document).on("mousemove", function (event) {
46                         var pointX = event.clientX+$(document).scrollLeft();
47                         var pointY = event.clientY+$(document).scrollTop();
48                         nowLeft = pointX - options.cameraW / 2;
49                         nowTop = pointY - options.cameraH / 2;
50                         if (nowLeft <= objLeft) { nowLeft = objLeft; }
51                         else if (nowLeft >= cameraMaxLeft) { nowLeft = cameraMaxLeft; }
52                         if (nowTop <= objTop) { nowTop = objTop; }
53                         else if (nowTop >= cameraMaxTop) { nowTop=cameraMaxTop;}                        
54                         objFdjcamera.css({ left: nowLeft + "px", top: nowTop + "px" });
55                         nowLeft=(nowLeft-objLeft)*options.zoom;
56                         nowTop=(nowTop-objTop)*options.zoom;                                   
57                         $("img",$(".gysFdjBox[" + fdAttr + "=" + fdCount + "]")).css({ "margin-top": -nowTop + "px", "margin-left": -nowLeft + "px" });
58                     });
59                 });
60                 objFdjcamera.on("mouseleave", function () {
61                     $(document).off("mousemove");
62                     objFdjcamera.hide();
63                     $(".gysFdjBox["+fdAttr+"="+fdCount+"]").hide();
64                 });
65             }
66         })(jQuery);

1 .test{ width:300px;height:400px; overflow:hidden;}

1 <div class="test"><img src="../img/x.jpg"  alt="小图"/></div>

1 $(function () {
2             $(".test").gysFdj({ zoom: 2 });             3         });