好用并强大的图片插件：PhotoSwipe.js

插件下载地址：https://pan.baidu.com/s/1kfnX6L54kU_NmQTZdLl94w

密码：zn2b

var initPhotoSwipeFromDOM = function(gallerySelector) {
        // 解析来自DOM元素幻灯片数据（URL，标题，大小...）
        var parseThumbnailElements = function(el) {
            var thumbElements = el.childNodes,
                numNodes = thumbElements.length,
                items = [],
                figureEl,
                linkEl,
                size,
                item,
                divEl;
            for(var i = 0; i < numNodes; i++) {
                figureEl = thumbElements[i]; // 
 element
                // 仅包括元素节点
                if(figureEl.nodeType !== 1) {
                    continue;
                }
                divEl = figureEl.children[0];
                linkEl = divEl.children[0]; //  element
                var img = new Image();
                img.src = linkEl.getAttribute('href');

                linkEl.setAttribute('data-size', img.naturalWidth + 'x' + img.naturalHeight);

                size = linkEl.getAttribute('data-size').split('x');
                // 创建幻灯片对象
                item = {
                    src: linkEl.getAttribute('href'),
                    w: parseInt(size[0], 10),
                    h: parseInt(size[1], 10)
                };
                if(figureEl.children.length > 1) {
                    item.title = figureEl.children[1].innerHTML;
                }
                if(linkEl.children.length > 0) {
                    //  缩略图节点, 检索缩略图网址
                    item.msrc = linkEl.children[0].getAttribute('src');
                }
                item.el = figureEl; // 保存链接元素 for getThumbBoundsFn
                items.push(item);
            }
            return items;
        };




        // 查找最近的父节点
        var closest = function closest(el, fn) {
            return el && ( fn(el) ? el : closest(el.parentNode, fn) );
        };

        // 当用户点击缩略图触发
        var onThumbnailsClick = function(e) {
            e = e || window.event;
            e.preventDefault ? e.preventDefault() : e.returnValue = false;
            var eTarget = e.target || e.srcElement;
            var clickedListItem = closest(eTarget, function(el) {
                return (el.tagName && el.tagName.toUpperCase() === 'FIGURE');
            });
            if(!clickedListItem) {
                return;
            }
            var clickedGallery = clickedListItem.parentNode,
                childNodes = clickedListItem.parentNode.childNodes,
                numChildNodes = childNodes.length,
                nodeIndex = 0,
                index;
            for (var i = 0; i < numChildNodes; i++) {
                if(childNodes[i].nodeType !== 1) {
                    continue;
                }
                if(childNodes[i] === clickedListItem) {
                    index = nodeIndex;
                    break;
                }
                nodeIndex++;
            }
            if(index >= 0) {
                openPhotoSwipe( index, clickedGallery );
            }
            return false;
        };

        var photoswipeParseHash = function() {
            var hash = window.location.hash.substring(1),
                params = {};
            if(hash.length < 5) {
                return params;
            }
            var vars = hash.split('&');
            for (var i = 0; i < vars.length; i++) {
                if(!vars[i]) {
                    continue;
                }
                var pair = vars[i].split('=');
                if(pair.length < 2) {
                    continue;
                }
                params[pair[0]] = pair[1];
            }
            if(params.gid) {
                params.gid = parseInt(params.gid, 10);
            }
            return params;
        };

        var openPhotoSwipe = function(index, galleryElement, disableAnimation, fromURL) {
            var pswpElement = document.querySelectorAll('.pswp')[0],
                gallery,
                options,
                items;
            items = parseThumbnailElements(galleryElement);
            // 这里可以定义参数
            options = {
                index: 0,
                barsSize: {
                    top: 100,
                    bottom: 100
                },
                //全屏模式关闭
                fullscreenEl : false,
                //点击图片关闭
                tapToClose: true,
                //分享按钮
                shareButtons: [
                    // {id:'wechat', label:'分享微信', url:'#'},
                    // {id:'weibo', label:'新浪微博', url:'#'},
                    {id:'download', label:'保存图片', url:'{{raw_image_url}}', download:true}
                ],
                galleryUID: galleryElement.getAttribute('data-pswp-uid'),
                getThumbBoundsFn: function(index) {
                    var thumbnail = items[index].el.getElementsByTagName('img')[0], // find thumbnail
                        pageYScroll = window.pageYOffset || document.documentElement.scrollTop,
                        rect = thumbnail.getBoundingClientRect();
                    return {x:rect.left, y:rect.top + pageYScroll, w:rect.width};
                }
            };
            if(fromURL) {
                if(options.galleryPIDs) {
                    for(var j = 0; j < items.length; j++) {
                        if(items[j].pid == index) {
                            options.index = j;
                            break;
                        }
                    }
                } else {
                    options.index = parseInt(index, 10) - 1;
                }
            } else {
                options.index = parseInt(index, 10);
            }
            if( isNaN(options.index) ) {
                return;
            }
            if(disableAnimation) {
                options.showAnimationDuration = 0;
            }
            gallery = new PhotoSwipe( pswpElement, PhotoSwipeUI_Default, items, options);
            gallery.init();
        };

        var galleryElements = document.querySelectorAll( gallerySelector );
        for(var i = 0, l = galleryElements.length; i < l; i++) {
            galleryElements[i].setAttribute('data-pswp-uid', i+1);
            galleryElements[i].onclick = onThumbnailsClick;
        }
        var hashData = photoswipeParseHash();
        if(hashData.pid && hashData.gid) {
            openPhotoSwipe( hashData.pid ,  galleryElements[ hashData.gid - 1 ], true, true );
        }
    };

//图片预览
                initPhotoSwipeFromDOM('.my-gallery');

Git地址：https://github.com/dimsemenov/photoswipe