【Web开发】jquery图片放大镜效果制作变焦镜头图片放大

jquery图片放大镜效果制作变焦镜头图片放大实现

整体步骤流程：

1. 前端html实现

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>前端界面jquery实现变焦放大图片细节效果</title>

<style type="text/css">
.content{width:960px;margin:0 auto;}
.content li{width:450px;height:350px;float:left;list-style:none;}
.zoom{display:inline-block;}
.zoom:after{content:'';display:block;width:33px;height:33px;position:absolute;top:0;right:0;}
.zoom img{display:block;}
.zoom img::selection{background-color:transparent;}
#image3 img:hover{cursor:url(images/grab.cur), default;}
#image3 img:active{cursor:url(images/grabbed.cur), default;}
</style>

<script type="text/javascript" src='js/jquery.min.js'></script>
<script type="text/javascript" src='js/jquery.zoombie.js'></script>
<script type="text/javascript">
    $(document).ready(function () {

        $('#image1').zoombie();

        $('#image2').zoombie({ on: 'click' });

        $('#image3').zoombie({ on: 'grab' });

        $('#image4').zoombie({ on: 'toggle' });

    });
</script>

<script type="text/javascript" language="javascript">
    $(function () {
        $("#img_01").zoombieLens();

        $("#img_02").zoombieLens({ Size: 500 });

        $("#img_03").zoombieLens({ imageSrc: "images/校园逸夫楼1.jpg" });

        $("#img_04").zoombieLens({ borderSize: 15, borderColor: "#06f" });

    });
</script>

</head>
<body>

<ul class="content">
	<!--<li>
		<span class='zoom' id='image1'>
			<img src='images/校园逸夫楼1.jpg' id='img1' width='426' height='241' style="border: 2px solid #666666;" alt='Daisy on the Ohoopee'/>
		</span>
		<pre>$('#image1').zoombie();</pre>
		<pre>鼠标经过放大细节</pre>
	</li>

	<li>
		<span id='image2' class='zoom'>
			<img src='images/校园逸夫楼1.jpg' id='img2' width='426' height='241' style="border: 2px solid #666666;" alt='Daisy on the Ohoopee'/>		
		</span>
		<pre>$('#image2').zoombie({ on: 'click' });</pre>
		<pre>鼠标单击放大细节</pre>
	</li>
	<li>
		<span class='zoom' id='image3'>
			<img src='images/校园逸夫楼1.jpg' id='img3' width='426' height='241' style="border: 2px solid #666666;" alt='Daisy on the Ohoopee'/>
		</span>
		<pre>$('#image3').zoombie({ on: 'grab' });</pre>
		<pre>鼠标单击放大细节</pre>
	</li>
	<li>
		<span class='zoom' id='image4'>
			<img src='images/校园逸夫楼1.jpg' id='img4' width='426' height='241' style="border: 2px solid #666666;" alt='Daisy on the Ohoopee'/>
		</span>
		<pre>$('#image4').zoombie({ on:'toggle' });</pre>
		<pre>鼠标单击放大细节</pre>
	</li>-->
	<li>
		<img id="img_01" src="images/校园逸夫楼1.jpg" width='426' height='241' style="border: 2px solid #666666;"  alt='Daisy on the Ohoopee' />
		<!--<pre>$("#img_01").zoombieLens();</pre>-->
		<pre>鼠标经过放大细节</pre>
	</li>
	<li>
		<img id="img_02" src="images/校园逸夫楼1.jpg" width='426' height='241'style="border: 2px solid #666666;"  alt='Daisy on the Ohoopee'/>
		<!--<pre>$("#img_02").zoombieLens({ Size: 2000 });</pre>-->
		<pre>鼠标经过放大细节</pre>
	</li>
	<li>
		<img id="img_03" src="images/校园逸夫楼1.jpg" width='426' height='241' style="border: 2px solid #666666;"  alt='Daisy on the Ohoopee'/>
		<!--<pre>$("#img_03").zoombieLens({ imageSrc: "可爱小刺猬.jpg" });</pre>-->
		<pre>鼠标经过放大细节</pre>
	</li>
	<li>
		<img id="img_04" src="images/校园逸夫楼1.jpg" width='426' height='241' style="border: 2px solid #00ff21;" alt='Daisy on the Ohoopee' />
		<!--<pre>$("#img_04").zoombieLens({ borderSize: 15, borderColor: "#06f" });</pre>-->
		<pre>鼠标经过放大细节</pre>
	</li>
</ul>

</body>
</html>

2. JavaScript实现

2.1 js/jquery.zoombie.js


(function ($) {
    $.fn.zoombieLens = function (options) {

        var defaults = {
            Size: 100,
            borderSize: 4,
            borderColor: "#888"
        };
        var options = $.extend(defaults, options);
        var lensType = "background-position: 0px 0px;width: " + String(options.Size) + "px;height: " + String(options.Size)
            + "px;float: left;display: none;border-radius: " + String(options.Size / 2 + options.borderSize)
            + "px;border: " + String(options.borderSize) + "px solid " + options.borderColor
            + ";background-repeat: no-repeat;position: absolute;";

        return this.each(function () {
            obj = $(this);

            var offset = $(this).offset();

            // Creating lens
            var target = $("<div style='" + lensType + "' class='" + options.lensCss + "'>&nbsp;</div>").appendTo($(this).parent());
            var targetSize = target.size();

            // Calculating actual size of image
            var imageSrc = options.imageSrc ? options.imageSrc : $(this).attr("src");
            var imageTag = "<img style='display:none;' src='" + imageSrc + "' />";

            var widthRatio = 0;
            var heightRatio = 0;

            $(imageTag).load(function () {
                widthRatio = $(this).width() / obj.width();
                heightRatio = $(this).height() / obj.height();
            }).appendTo($(this).parent());

            target.css({ backgroundImage: "url('" + imageSrc + "')" });

            target.mousemove(setImage);
            $(this).mousemove(setImage);

            function setImage(e) {

                var leftPos = parseInt(e.pageX - offset.left);
                var topPos = parseInt(e.pageY - offset.top);

                if (leftPos < 0 || topPos < 0 || leftPos > obj.width() || topPos > obj.height()) {
                    target.hide();
                }
                else {
                    target.show();

                    leftPos = String(((e.pageX - offset.left) * widthRatio - target.width() / 2) * (-1));
                    topPos = String(((e.pageY - offset.top) * heightRatio - target.height() / 2) * (-1));
                    target.css({ backgroundPosition: leftPos + 'px ' + topPos + 'px' });

                    leftPos = String(e.pageX - target.width() / 2);
                    topPos = String(e.pageY - target.height() / 2);
                    target.css({ left: leftPos + 'px', top: topPos + 'px' });
                }
            }
        });
    };
})(jQuery);

(function ($) {
	var defaults = {
		url: false,
		callback: false,
		target: false,
		duration: 120,
		on: 'mouseover' // other options: 'grab', 'click', 'toggle'
	};

	$.zoombie = function(target, source, img) {
		var outerWidth,
			outerHeight,
			xRatio,
			yRatio,
			offset,
			position = $(target).css('position');

		
		$(target).css({
			position: /(absolute|fixed)/.test() ? position : 'relative',
			overflow: 'hidden'
		});

		$(img)
			.addClass('zoomImg')
			.css({
				position: 'absolute',
				top: 0,
				left: 0,
				opacity: 0,
				width: img.width,
				height: img.height,
				border: 'none',
				maxWidth: 'none'
			})
			.appendTo(target);

		return {
			init: function() {
				outerWidth = $(target).outerWidth();
				outerHeight = $(target).outerHeight();
				xRatio = (img.width - outerWidth) / $(source).outerWidth();
				yRatio = (img.height - outerHeight) / $(source).outerHeight();
				offset = $(source).offset();
			},
			move: function (e) {
				var left = (e.pageX - offset.left),
					top = (e.pageY - offset.top);

				top = Math.max(Math.min(top, outerHeight), 0);
				left = Math.max(Math.min(left, outerWidth), 0);

				img.style.left = (left * -xRatio) + 'px';
				img.style.top = (top * -yRatio) + 'px';
			}
		};
	};

	$.fn.zoombie = function (options) {
		return this.each(function () {
			var
			settings = $.extend({}, defaults, options || {}),
			//target will display the zoomed iamge
			target = settings.target || this,
			//source will provide zoom location info (thumbnail)
			source = this,
			img = new Image(),
			$img = $(img),
			mousemove = 'mousemove',
			clicked = false;

			// If a url wasn't specified, look for an image element.
			if (!settings.url) {
				settings.url = $(source).find('img').attr('src');
				if (!settings.url) {
					return;
				}
			}

			img.onload = function () {
				var zoombie = $.zoombie(target, source, img);

				function start(e) {
					zoombie.init();
					zoombie.move(e);

					// Skip the fade-in for IE8 and lower since it chokes on fading-in
					// and changing position based on mousemovement at the same time.
					$img.stop()
					.fadeTo($.support.opacity ? settings.duration : 0, 1);
				}

				function stop() {
					$img.stop()
					.fadeTo(settings.duration, 0);
				}

				if (settings.on === 'grab') {
					$(source).mousedown(
						function (e) {
							$(document).one('mouseup',
								function () {
									stop();

									$(document).unbind(mousemove, zoombie.move);
								}
							);

							start(e);

							$(document)[mousemove](zoombie.move);

							e.preventDefault();
						}
					);
				} else if (settings.on === 'click') {
					$(source).click(
						function (e) {
							if (clicked) {
								// bubble the event up to the document to trigger the unbind.
								return;
							} else {
								clicked = true;
								start(e);
								$(document)[mousemove](zoombie.move);
								$(document).one('click',
									function () {
										stop();
										clicked = false;
										$(document).unbind(mousemove, zoombie.move);
									}
								);
								return false;
							}
						}
					);
				} else if (settings.on === 'toggle') {
					$(source).click(
						function (e) {
							if (clicked) {
								stop();
							} else {
								start(e);
							}
							clicked = !clicked;
						}
					);
				} else {
					zoombie.init(); 

					$(source).hover(
						start,
						stop
					)[mousemove](zoombie.move);
				}

				if ($.isFunction(settings.callback)) {
					settings.callback.call(img);
				}
			};

			img.src = settings.url;
		});
	};

	$.fn.zoombie.defaults = defaults;

}(window.jQuery));