很早就想分享给大家了。由于比较忙且懒-，
之前开发有这样一个需求，像微信朋友圈一样发布动态的一个功能。刚开始想尝试百度下有没有合适的插件。百度了很久都没找到合适的，大都是可以上传不能预览。或者是预览功能有问题。无奈之下，还是靠自己吧。
其实想一想还是挺简单，上传就不用说了通过input的file获取到文件再通过fileReader将图片路径转成Base64。比较大的难题是点击图片预览，且可以滑动。

• 基本思路就是先写好基本样式（遮罩啊等等）然后通过当前图片点击获取到图片路径的集合，拿到集合后写个轮播，并且通过一个布尔值控制遮罩层的显示和隐藏。
• 好吧以上是我的意淫。试了以后是有效果。但是不完美，图片放大事件啥的不知道咋弄，后来用了个比较成熟的PhotoSwipe,研究了一番加上自己稍微的小修改做出来了。给它个赞吧。
  源码链接戳这里
  预览地址戳这里～建议将浏览器切成手机分辨率
  路过的亲给个star吧~~

发布页.jpeg

图片上传,可一次性上传多张.jpeg

图片预览.jpeg

图片预览.jpeg

发布动态中.jpeg

发布成功.jpeg

//upload.vue
<!--
Description 图片上传
@authors Benny
@date    2018-05-08 12:57:08
@version 1.0.0
-->
<template>
    <div id="imgUploader">
        <div class="file-list">
          <!-- <section class="file-item draggable-item" v-for="(item,index) in files" :key="index"> -->
            <div class="thumbnails my-gallery">
                <figure itemprop="associatedMedia" itemscope  class="thumbnail" v-for="(item,index) in files" :key="index">
                    <a :href="item.src" itemprop="contentUrl" data-size="400x400" class="img-wrapper">
                        <img :src="item.src" itemprop="thumbnail"  />
                        <!-- <div :style="{background:'url('+item.src+')  no-repeat',  backgroundPosition:'center center',backgroundSize:'cover'}" style="width:100%;height:110px;" itemprop="thumbnail"></div> -->
                    </a>
                    <span class="file-remove" @click="remove(index,$event)">×</span>
                </figure>
                <section class="thumbnail" v-if="this.files.length < 9">
                  <div class="add">
                    <span>+</span>
                    <!-- accept="image/jpeg,image/png" capture="camera" -->
                    <input type="file" @change="selectImgs()" multiple accept="image/*" ref="file">
                  </div>
                </section>
            </div>
            <!-- <img :src="item.src" alt="" ondragstart="return false;">
            <span class="file-remove" @click="remove(index)">×</span> -->
          <!-- </section> -->
          <!-- PhotoSwipe插件需要的元素， 一定要有类名 pswp -->
          <div class="pswp" tabindex="-1" role="dialog" aria-hidden="true">
              <div class="pswp__bg"></div>
              <div class="pswp__scroll-wrap">
                  <div class="pswp__container">
                      <div class="pswp__item"></div>
                      <div class="pswp__item"></div>
                      <div class="pswp__item"></div>
                  </div>
                  <!-- 预览区域顶部的默认UI，可以修改 -->
                  <div class="pswp__ui pswp__ui--hidden">
                      <div class="pswp__top-bar">
                          <!--  与图片相关的操作 -->
                          <div class="pswp__counter"></div>
                          <button class="pswp__button pswp__button--close" title="Close (Esc)"></button>
                          <!--将分享按钮去掉 -->
                          <!-- <button class="pswp__button pswp__button--share" title="Share"></button>
                          <button class="pswp__button pswp__button--fs" title="Toggle fullscreen"></button>
                          <button class="pswp__button pswp__button--zoom" title="Zoom in/out"></button> -->
                          <div class="pswp__preloader">
                              <div class="pswp__preloader__icn">
                                  <div class="pswp__preloader__cut">
                                      <div class="pswp__preloader__donut"></div>
                                  </div>
                              </div>
                          </div>
                      </div>
                      <div class="pswp__share-modal pswp__share-modal--hidden pswp__single-tap">
                          <div class="pswp__share-tooltip"></div>
                      </div>
                      <button class="pswp__button pswp__button--arrow--left" title="Previous (arrow left)"></button>
                      <button class="pswp__button pswp__button--arrow--right" title="Next (arrow right)"></button>
                      <div class="pswp__caption">
                          <div class="pswp__caption__center"></div>
                      </div>
                  </div>
              </div>
          </div>
        </div>
    </div>
</template>


<script src='scripts/shared/upload'/>
<style src='styles/shared/upload.less' lang="less" scoped>

//upload.js
//注: photoswipe 需要npm install 安装一下,主要是用于图片预览
import PhotoSwipe from "photoswipe";   
import PhotoSwipeUI_Default from "photoswipe/dist/photoswipe-ui-default";
import "photoswipe/dist/photoswipe.css";
import "photoswipe/dist/default-skin/default-skin.css";
import { Toast } from 'mint-ui';//这块可以不用,只是提示框
export default {
    data() {
        return {
            lang: this.$lang('dynamic'),//语言包
            files: [], // 文件缓存
            index: 0, // 序列号
            maxLength: 9, // 图片最大数量
            maxSize: 10240000, //图片限制为10M内
        };
    },
    methods: {
        //选择图片
        selectImgs() {
            let fileList = this.$refs.file.files
            if (fileList.length > 9) { //如果大于9张,做出提醒
                alert(this.lang.dynamic_upload_tips)
            }
            let tempList = []; //每次点击+号后选择的图片信息
            for (let i = 0, len = fileList.length; i < len; i++) {
                let fileItem = {
                    Id: this.index++,
                    name: fileList[i].name,
                    size: fileList[i].size,
                    file: fileList[i]
                }
                //将图片文件转成Base64
                let reader = new FileReader()
                reader.onloadend = (e) => {
                    //压缩图片并存到fileItem中
                    this.getBase64(e.target.result).then((url) => {
                        this.$set(fileItem, 'src', url)
                    })

                }
                //判断图片大小是否超出限制
             if (fileItem.size > this.maxSize) {
                    Toast(this.lang.dynamic_over_size)
                } else {
                    reader.readAsDataURL(fileList[i])
                    tempList.push(fileItem)
                    this.files.push(fileItem)
                }
            }
            setTimeout(() => {
                this.$emit('getFiles', tempList)
            }, 300)
            this.files.splice(9)
        },

        // 图片压缩并保存到files
        getBase64(url) {
            let self = this;
            let Img = new Image(),
                dataURL = '';
            Img.src = url;
            let p = new Promise(function (resolve, reject) {
                Img.onload = function () { //要先确保图片完整获取到，这是个异步事件
                    let canvas = document.createElement("canvas"), //创建canvas元素
                        width = Img.width, //确保canvas的尺寸和图片一样
                        height = Img.height;
                    // 默认将长宽设置为图片的原始长宽，这样在长宽不超过最大长度时就不需要再处理
                    let ratio = width / height,
                        maxLength = 1000,
                        newHeight = height,
                        newWidth = width;
                    // 在长宽超过最大长度时，按图片长宽比例等比缩小
                    if (width > maxLength || height > maxLength) {

                        if (width > height) {
                            newWidth = maxLength;
                            newHeight = maxLength / ratio;
                        } else {
                            newWidth = maxLength * ratio;
                            newHeight = maxLength;
                        }
                    }
                    canvas.width = newWidth;
                    canvas.height = newHeight;
                    canvas.getContext("2d").drawImage(Img, 0, 0, newWidth, newHeight); //将图片绘制到canvas中
                    dataURL = canvas.toDataURL('image/jpeg', 0.5); //转换图片为dataURL
                    resolve(dataURL);
                };
            });
            return p
        },
        // 移除图片
        remove(index, e) {
            e.stopPropagation(); //阻止
            this.files.splice(index, 1)
            setTimeout(() => {
                this.$emit('removeFiles', index)
            }, 300)
        },
        //引入photoSwipe(可预览、滑动)
        initPhotoSwipeFromDOM(gallerySelector) {
            var parseThumbnailElements = function (el) {
                var thumbElements = el.childNodes,
                    numNodes = thumbElements.length,
                    items = [],
                    figureEl,
                    linkEl,
                    size,
                    item;
                for (var i = 0; i < numNodes - 1; i++) {
                    figureEl = thumbElements[i];
                    if (figureEl.nodeType !== 1) {
                        continue;
                    }
                    linkEl = figureEl.children[0];
                    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");
                    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) {
                        item.msrc = linkEl.children[0].getAttribute("src");
                    }
                    item.el = figureEl;
                    items.push(item);
                }
                return items;
            };
            var closest = function closest(el, fn) {
                return el && (fn(el) ? el : closest(el.parentNode, fn));
            };
            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, e) {
                    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);
                options = {
                    history: false,
                    tapToClose: true,
                    galleryUID: galleryElement.getAttribute("data-pswp-uid"),
                    getThumbBoundsFn: function (index) {
                        var thumbnail = items[index].el.getElementsByTagName("img")[0],
                            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
                );
            }
        }

    },
    mounted() {
        this.initPhotoSwipeFromDOM(".my-gallery");
    }
};

//upload.less
//样式块命名啥的不太规范.建议花小小的时间重写下 
#imgUploader {
    flex: 1;
    margin-top: auto;
    padding-left:10px;
    .file-list {
      padding: 10px 0px;
      &::after {
        content: "";
        display: block;
        clear: both;
        visibility: hidden;
        line-height: 0;
        height: 0;
        font-size: 0;
      }
        .file-remove {
          position: absolute;
          font-size: 12px;
          right: 5px;
          top: 1px;
          width: 14px;
          height: 14px;
          color: white;
          cursor: pointer;
          line-height: 12px;
          background: rgba(0, 0, 0, 0.25);
          z-index: 1000;
        }
  
        &:hover .file-remove {
          display: inline;
        }
      }
    }
  .add {
    width: 100%;
    height: 110px;
    float: left;
    text-align: center;
    line-height: 110px;
    // font-size: 1.4rem;
    font-weight: 100;
    cursor: pointer;
    border: 1px dashed #ccc;
    color: #999;
    position: relative;
    // background: #f2f2f2;
    .fa {
      font-size: 1.4em;
      color: #7dd2d9;
    }
  }
  .uploadBtn {
    position: relative;
    .empty {
      position: absolute;
      right: 0;
      bottom: 0;
      background-color: #eee;
      color: #fff;
      padding: 0.2em 1em;
    }
  }
  
  .thumbnails {
    width: 100%;
    display: -webkit-box;
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
    -webkit-flex-wrap: wrap;
    -ms-flex-wrap: wrap;
    flex-wrap: wrap;
   .thumbnail {
      position: relative;
      margin:0 0 10px 0;
      padding-right: 5px;
      width: 33%;
      box-sizing: border-box;
      height: 110px;
      // &:nth-child(3n){
      //   padding-right: 0;
      // }
      .img-wrapper{
        position: relative;
        display: flex;
        height: 110px;
        img {
          width: auto;
          height: auto;
          width: 100%;
          max-width: 100%;
          max-height: 100%;
        }
      }
    }
  }
  input[type="file"] {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 110px;
    opacity: 0;
  }

主要的上传图片预览就是以上部分啦,不过真正的上传功能还没开始。上边点击+号上传图片后,会触发父组件的getFiles方法,父组件会通过getFiles获取组件里边上传图片的信息包括base64,文件名等,然后再在里头处理上传操作。

//父组件 create.vue
<!--
Description 发布动态
@authors Benny
@date    2018-04-23 10:31:30
@version 1.0.0
-->
<template>
  <div id="dynamic_create">
    <mt-field  v-model="dynamicContent" :placeholder="lang.dynamic_moments_thought" type="textarea" rows="4" ></mt-field>
    <uploader @getFiles='getImageList' @removeFiles='removeImage'></uploader>
    <div class="btn-wrapper">
        <!-- <mt-button class='btn-send' size="large" type="primary" @click="send">{{this.lang.dynamic_release}}</mt-button> -->
        <load-button :class="isSubmit ? 'text-666 btn-send' : 'bg-blue text-white btn-send'" :loading="isSubmit" @callback="send" :text="lang.dynamic_release"></load-button>
    </div>
  
  </div>
</template>

<script src='scripts/profile/dynamic/create'/>
<style src='styles/profile/dynamic/create.less' scoped lang="less"/>

//create.js
//主要是在getImageList方法
 getImageList(files) {
            this.$nextTick(() => {
                for (let i = 0, len = files.length; i < len; i++) {
                    this.imgList.push(files[i].src.split('base64,')[1])
                    //上传图片
                    this._getFileCode({
                        Base64Str: files[i].src.split('base64,')[1],
                        AttachmentType: this.$enums.AttachmentType.Activity
                    })
                }
            })
        },

以上就是核心代码啦,有什么不对或者可以改进的地方可以评论一起探讨哦～
有点瑕疵的地方就是上传图片预览的时候,图片还是有点拉伸,有木有什么办法可以解决呢？类似微信那种 上传完后展示裁剪图片的中心块。