说在前面

网上有很多种文件上传的方法，根据公司最近的业务需求，要求实现多种文件的上传，在实现过程中，查阅了很多资料，最后，终于把功能实现了，开心！

<template>
  <div>
    <v-header :left-text="`上传${columnName}`"></v-header>

    <div class="upload">
      <div v-if="columnName === '视频'">
        <div class="forPreview_video" v-for="(item, index) in uploadVideoList" :key="index">
          <video :src="videoSrc"></video>
          <van-icon name="delete" @click="delBtn(index)" class="delte"/>
        </div>
        <van-uploader v-show="uploadVideoList.length < 2" preview-size="80px" accept="video/*" :before-read="beforeRead" :after-read="afterRead"></van-uploader>
      </div>

      <div v-if="columnName === '文档'">
        <div class="forPreview_doc" v-for="(item, index) in uploadDocList" :key="index">
          <img src="../../assets/img/resource_doc_b@2x.png" alt="">
          <span>{{item.name}}</span>
          <span>{{item.size | formatSize}}</span>
          <van-icon name="delete" @click="delBtn(index)" class="delte"/>
        </div>
        <van-uploader v-show="uploadDocList.length < 2" preview-size="80px" accept=".doc, .docx, .xml, .xlsx, .pdf" :before-read="beforeRead" :after-read="afterRead"></van-uploader>
      </div>

      <div v-if="columnName === '音频'">
        <div class="forPreview_audio" v-for="(item, index) in uploadAudioList" :key="index">
          <img src="../../assets/img/resource_audio@2x.png" alt="">
          <span>{{item.name}}</span>
          <span>{{item.size | formatSize}}</span>
          <van-icon name="delete" @click="delBtn(index)" class="delte"/>
        </div>
        <van-uploader v-show="uploadAudioList.length < 2" preview-size="80px" accept="audio/*" :before-read="beforeRead" :after-read="afterRead"></van-uploader>
      </div>

      <div v-if="columnName === '图片'">
        <div class="forPreview_pic" v-for="(item, index) in uploadPicList" :key="index">
          <img :src="picSrc" alt="">
          <van-icon name="delete" @click="delBtn(index)" class="delte"/>
        </div>
        <van-uploader v-show="uploadPicList.length < 2" accept="image/*" preview-size="80px" :before-read="beforeRead" :after-read="afterRead"></van-uploader>
      </div>

      <div class="diy-submit">
        <van-button @click="doSubmit($event)">提交</van-button>
      </div>
    </div>
  </div>
</template>

上述html代码是在同一页面根据前一页面传回的columnName的值来判断需要上传哪种类型文件。

<script>
  import VHeader from '../../common/header'
  import {classifyList, uploadFile, addResources} from '../../http/mock'
  import Toast from 'vant'
  export default {
    name: "uploadFile",
    components: {
      VHeader
    },
    data(){
      return{
        tagList: [], 
        uploadTitle: '',
        currentTag: null,
        tagId: null,
        columnName: localStorage.getItem('columnName'),
        fileIdArr: [],

        uploadVideoList: [], // 选中的上传视频列表
        videoSrc: '',  // 选中的视频的src，用来显示视频
        uploadDocList: [], // 选中的上传文档列表
        uploadAudioList: [], // 选中的上传音频列表
        uploadPicList: [], // 选中的上传图片列表
        picSrc: '', // 选中的图片的src，用来显示图片缩略图
      }
    },
    filters: {
      formatSize(val) { // 格式化文件大小
        if (val > 0) {
          return (val / 1024 / 1024).toFixed(2) + 'M';
        } else {
          return '0M';
        }
      },
    },
    methods: {
      // vant上传文件前校验文件事件
      // 文件选中后先提交给后台，后台根据选中的文件，返回数组（这一业务根据后台而定）
      beforeRead(file){
        let formData = new FormData(); // 为上传文件定义一个formData对象
        let config = {
          headers: {
            'Content-Type': 'multipart/form-data'
          }
        };
        let uploadUrl = URL.createObjectURL(file); // 将选中的上传文件转化为二进制文件，显示在页面上
        if(this.columnName === '视频'){
          this.uploadVideoList.push(file);
          this.videoSrc = uploadUrl;
          // 这里使用foreach是为了将选中的多个文件都添加进定义的formdata变量中
          this.uploadVideoList.forEach(item => {
            formData.append(item.name, item)
          })
        }else if(this.columnName === '文档'){
          this.uploadDocList.push(file);
          this.uploadDocList.forEach(item => {
            formData.append(item.name, item)
          })
        }else if(this.columnName === '音频'){
          this.uploadAudioList.push(file);
          this.uploadAudioList.forEach(item => {
            formData.append(item.name, item)
          })
        }else if(this.columnName === '图片'){
          this.uploadPicList.push(file);
          this.picSrc = uploadUrl;
          this.uploadPicList.forEach(item => {
            formData.append(item.name, item)
          })
        }


        // formData.append(file.name, file); // 单个文件上传时可以这么写，上面的foreach就可以删掉
        this.$api.post(uploadFile, formData, config).then(res => {
          this.fileIdArr = res.data.data;  // 把選中的文件傳送給後台
        }).catch(err => {
          Toast('文件上傳失敗！')
        })
      },
      // 删除待上传的文件
      delBtn(index){
        if(this.columnName === '视频'){
          // 先判断当前的选中的索引是否是在有效范围中，如果不是则跳出方法 
          if(isNaN(index) || index >= this.uploadVideoList.length){
            return false;
          }
          let tmp = [];
          // 将没被选中的上传文件存放进一个临时数组中
          for(let i = 0; i < this.uploadVideoList.length; i++){
            if(this.uploadVideoList[i] !== this.uploadVideoList[index]){
              tmp.push(this.uploadVideoList[i]);
            }
          }
          // 存放当前未被选中的上传文件
          this.uploadVideoList = tmp;
        }

        if(this.columnName === '文档'){
          console.log(this.uploadDocList.length)
          if(isNaN(index) || index >= this.uploadDocList.length){
            return false;
          }
          let tmp = [];
          for(let i = 0; i < this.uploadDocList.length; i++){
            if(this.uploadDocList[i] !== this.uploadDocList[index]){
              tmp.push(this.uploadDocList[i]);
            }
          }
          this.uploadDocList = tmp;
        }

        if(this.columnName === '音频'){
          if(isNaN(index) || index >= this.uploadAudioList.length){
            return false;
          }
          let tmp = [];
          for(let i = 0; i < this.uploadAudioList.length; i++){
            if(this.uploadAudioList[i] !== this.uploadAudioList[index]){
              tmp.push(this.uploadAudioList[i]);
            }
          }
          this.uploadAudioList = tmp;
        }

        if(this.columnName === '图片'){
          if(isNaN(index) || index >= this.uploadPicList.length){
            return false;
          }
          console.log('uuu')
          let tmp = [];
          for(let i = 0; i < this.uploadPicList.length; i++){
            if(this.uploadPicList[i] !== this.uploadPicList[index]){
              tmp.push(this.uploadPicList[i]);
            }
          }
          this.uploadPicList = tmp;
        }
      },
      doSubmit(){
        let params = {
          classify: this.tagId,    // 针对视频资源时对应的分类id
          file: this.fileIdArr,  // 选择完文件后，调用uploadFile这个接口，后端返回的数组
          resourceColumnId: JSON.parse(localStorage.getItem('columnId')),  // 资源栏目id(视频、图片、音频、文档)
          title: this.uploadTitle  // 上传时填写的标题
        };
        let columnName = localStorage.getItem('columnName')
        this.$api.post(addResources, params).then(res => {
          if(res.data.code === 1001){
            if(columnName === '视频'){
              this.$router.push({name: 'myVideo'});
            }else {
              this.$router.push({name: 'myResourceClassify'});
            }
          }
        }).catch(err => {
          console.log(err)
        })
      },
    },
    mounted(){
      this.getClassifyList();
    }
  }
</script>
<style lang="less" scoped>
  .upload{
    padding: 140px 36px 160px 36px;
    box-sizing: border-box;
  }

  .forPreview_video{
    position: relative;
    /*background: rgba(0,0,0,.7);*/
    video{
      width: 95%;
      max-height: 430px;
    }
    .delte{
      position: absolute;
      right: 0;
      bottom: 0;
    }
  }
  .forPreview_doc, .forPreview_audio{
    display: flex;
    margin-bottom: 10px;
    align-items: center;
    img{
      width: 56px;
      height: 56px;
      margin-right: 20px;
    }
    span:nth-of-type(1){
      flex: 1;
    }
    span:nth-of-type(2){
      margin-right: 20px;
    }
  }
  .forPreview_pic{
    display: flex;
    align-items: flex-end;
    img{
      width: 160px;
      height: 160px;
    }
  }

  .diy-detail{
    width: 100%;
    overflow: hidden;
    
    .btn{
      span{
        margin-bottom: 10px;
      }
    }
    .van-cell{
      background-color: #F0F0F0;
      border-radius: 35px;
      font-size: 26px;
      height: 69px;
      line-height: 69px;
      padding: 0 22px;
      color: #999;
    }
    .van-hairline--top-bottom::after, .van-hairline-unset--top-bottom::after {
      border-width: 0;
    }
    p{
      height: 64px;
      line-height: 64px;
      font-size: 32px;
      color: #333;
      position: relative;
      padding-left: 16px;
    }
    p::before{
      position: absolute;
      top: 0;
      left: 0;
      content: '*';
      color: #FF0000;
    }

    span{
      display: inline-block;
      width: 157px;
      background: #F0F0F0;
      border-radius: 35px;
      color: #999;
      font-size: 26px;
      padding: 14px 18px;
      margin-right: 28px;
      text-align: center;
    }
    .active{
      color: #fff;
      background: linear-gradient(to right,#FD5130,#FA6C34);
    }
  }
  .diy-submit {
    position: fixed;
    height: 150px;
    width: 90%;
    bottom: 0;
    background: #fff;

    .van-button {
      width: 100%;
      height: 90px;
      border-radius: 45px;
      font-size: 36px;
      color: #fff;
      background: linear-gradient(to right, #FD5130, #FA6C34);
      top: 50%;
      transform: translate(0, -50%);
    }
    .van-button--default {
      border: none;
    }
  }
</style>