jQuery放大镜插件

jQuery放大镜插件，demo地址：http://codepen.io/jonechen/pen/mEmJYJ，图片引用的外链，打开的速度可能有点慢；

CSS部分：

*{padding: 0; margin: 0; list-style: none;}
.img{ display: block;position: relative; }
.area{width:50px;height: 100px;background: red;opacity: 0.6;position: absolute;left: 0;top: 0;display: none;}
.box{margin: 50px; }

HTML部分：

<div class="box">
	<img src="http://i2.piimg.com/508767/48115abf1b2e9194.jpg"  >
</div>

JS插件部分：

(function($) {
	var Magnify = function(ele, options) {
		this.ele = ele;
		this.opt = options;
		this.defaults = {
			selector: 'img',
			boxWidth: 400, // 容器宽度
			width: 100, // 放大区域宽度
			height: 100, // 放大区域高度
			radius: 0, // 放大圆角
			backgroundColor: 'red' // 背景色
		};
		this.setting = $.extend(this.defaults, this.opt);
	}
	Magnify.prototype = {
		init: function() {
			var _self = this.ele;
			var isMove = false;
			_self.css('width', this.setting.boxWidth).addClass(this.setting.selector);
			_self.parent().css({
				position: "relative",
				width: _self.css('width'),
			});
			var src = _self.attr('src');
			$("<div class='area'></div><div class='bigPic'><img src=" + src + "></<div>").appendTo(_self.parent());
			var $area = _self.parent().find(".area");
			var $bigPic = _self.parent().find(".bigPic");
			$area.css({
				width: this.setting.width,
				height: this.setting.height,
				borderRadius: this.setting.radius,
				backgroundColor: this.setting.backgroundColor
			})
			var sw = $area.width(); //剪裁框宽度
			var sh = $area.height(); //剪裁框高度
			var smallBox_w = _self.parent().width(); //小框的宽度
			var smallBox_h = _self.parent().height(); //小框的高度
			var pw = $bigPic.find('img').width(); //大图的宽度
			var ph = $bigPic.find('img').height(); //大图的高度
			var scale = (smallBox_w / pw).toFixed(2);
			$bigPic.css({
				display: 'none',
				position: 'absolute',
				width: parseInt(sw / scale),
				height: parseInt(sh / scale),
				left: '102%',
				top: 0,
				overflow: 'hidden',
				borderRadius: this.setting.radius == 100 ? this.setting.radius + '%' : this.setting.radius
			})
			$bigPic.find('img').css({
				position: 'absolute',
			})
			_self.parent().on("mouseenter", function() {
				$area.show();
				isMove = true
			})
			_self.parent().on("mousemove", function(event) {
				if (isMove) {
					$bigPic.show();
					setPos(event, $(this), scale);
				}
			})
			_self.parent().on("mouseleave", function() {
				$bigPic.hide();
				$area.hide();
				isMove = false
			})
		},
		events: function() {
			this.init();
		},
	}

	function setPos(e, obj, scale) {
		var x = e.pageX - obj.offset().left,
			y = e.pageY - obj.offset().top,
			w = obj.find('.area').width(),
			h = obj.find('.area').height();
		if (x < w / 2) {
			x = 0
		} else if (x > obj.width() - w / 2) {
			x = obj.width() - w
		} else {
			x -= w / 2
		}
		if (y < h / 2) {
			y = 0
		} else if (y > obj.height() - h / 2) {
			y = obj.height() - h
		} else {
			y -= h / 2
		}
		obj.find('.area').css({
			left: x,
			top: y
		});
		obj.find('.bigPic').find('img').css({
			left: -x / scale,
			top: -y / scale,
		})
	}
	$.fn.Magnifying = function(options) {
		var Magnifies = new Magnify(this, options);
		return Magnifies.events();
	}
})(jQuery);
// 插件调用 
$(function() {
	$(".box img").Magnifying();
})

默认参数API：

this.defaults = {
	selector: 'img',
	boxWidth: 400, // 容器宽度
	width: 100, // 放大区域宽度
	height: 100, // 放大区域高度
	radius: 0, // 放大圆角
	backgroundColor: 'red' // 背景色
};