Element UI 文件上传组件封装

<template>
  <div class="component-upload-image">
    <el-upload
      :action="uploadImgUrl"
      list-type="picture-card"
      :on-success="handleUploadSuccess"
      :before-upload="handleBeforeUpload"
      :limit="limit"
      :on-error="handleUploadError"
      :on-exceed="handleExceed"
      name="file"
      :on-remove="handleRemove"
      :show-file-list="true"
      :headers="headers"
      :file-list="fileList"
      :on-preview="handlePictureCardPreview"
      :on-progress="handleOnProgress"
      :class="{ hide: this.fileList.length >= this.limit }"
      :multiple="isMultiple"
    >
      <i class="el-icon-plus"></i>
      <p class="photo-text">点击上传</p>
    </el-upload>

    <!-- 上传提示 -->
    <div class="el-upload__tip" slot="tip" v-if="showTip">
      请上传
      <template v-if="fileSize">
        大小不超过 <b style="color: #f56c6c">{{ fileSize }}MB</b>
      </template>
      <template v-if="fileType">
        格式为 <b style="color: #f56c6c">{{ fileType.join('/') }}</b>
      </template>
      的文件
    </div>

    <!-- 预览 -->
    <el-dialog :visible.sync="dialogVisible" width="800" append-to-body custom-class="dialog-preview">
      <template #title>
        <div class="header">
          <span>预览</span>
        </div>
      </template>

      <img :src="dialogImageUrl" />
    </el-dialog>
  </div>
</template>

<script>
import { getToken } from '@/utils/auth'
import { cloneDeep } from 'lodash'

export default {
  name: 'ImageUpload',
  props: {
    value: [String, Object, Array],
    // 图片数量限制
    limit: {
      type: Number,
      default: 5,
    },
    // 大小限制(MB)
    fileSize: {
      type: Number,
      default: 5,
    },
    // 文件类型, 例如['png', 'jpg', 'jpeg']
    fileType: {
      type: Array,
      default: () => ['png', 'jpg', 'jpeg'],
    },
    // 是否显示提示
    isShowTip: {
      type: Boolean,
      default: true,
    },
    // 是否多选
    isMultiple: {
      type: Boolean,
      default: true,
    },
  },
  data() {
    return {
      dialogImageUrl: '',
      dialogVisible: false,
      hideUpload: false,
      baseUrl: process.env.VUE_APP_BASE_API,
      uploadImgUrl: process.env.VUE_APP_BASE_API + '/common/upload', // 上传的图片服务器地址
      headers: {
        Authorization: 'Bearer ' + getToken(),
      },
      fileList: [],
      uploadList: [],
      number: 0,
      isUploading: false,
    }
  },
  watch: {
    value: {
      handler(val) {
        if (val) {
          // 首先将值转为数组
          const list = Array.isArray(val) ? val : this.value.split(',')
          // 然后将数组转为对象数组
          this.fileList = list.map((item) => {
            if (typeof item === 'string') {
              if (item.indexOf(this.baseUrl) === -1) {
                item = { name: this.baseUrl + item, url: this.baseUrl + item }
              } else {
                item = { name: item, url: item }
              }
            }
            return item
          })
        } else {
          this.fileList = []
          return []
        }
      },
      deep: true,
      immediate: true,
    },
  },
  computed: {
    // 是否显示提示
    showTip() {
      return this.isShowTip && (this.fileType || this.fileSize)
    },
  },
  methods: {
    // 删除图片
    handleRemove(file, fileList) {
      const findex = this.fileList.map((f) => f.name).indexOf(file.name)
      if (findex > -1) {
        this.fileList.splice(findex, 1)
        this.$emit('input', cloneDeep(this.fileList))
      }
    },
    // 上传成功回调
    handleUploadSuccess(res) {
      this.isUploading = false
      this.uploadList.push({ name: res.fileName, url: this.baseUrl + res.fileName })
      if (this.uploadList.length === this.number) {
        this.fileList = this.fileList.concat(this.uploadList)
        this.uploadList = []
        this.number = 0
        this.$emit('input', cloneDeep(this.fileList))
      }
    },
    // 上传前文件校验
    handleBeforeUpload(file) {
      let isImg = false
      if (this.fileType.length) {
        let fileExtension = ''
        if (file.name.lastIndexOf('.') > -1) {
          fileExtension = file.name.slice(file.name.lastIndexOf('.') + 1)
        }
        isImg = this.fileType.some((type) => {
          if (file.type.indexOf(type) > -1) return true
          if (fileExtension && fileExtension.indexOf(type) > -1) return true
          return false
        })
      } else {
        isImg = file.type.indexOf('image') > -1
      }

      if (!isImg) {
        this.$message.error(`文件格式不正确, 请上传${this.fileType.join('/')}图片格式文件!`)
        return false
      }

      if (this.fileSize) {
        const isLt = file.size / 1024 / 1024 < this.fileSize
        if (!isLt) {
          this.$message.error(`上传头像图片大小不能超过 ${this.fileSize} MB!`)
          return false
        }
      }

      this.number++
    },
    // 文件个数超出
    handleExceed() {
      this.$message.error(`上传文件数量不能超过 ${this.limit} 个!`)
    },
    // 上传失败
    handleUploadError() {
      this.$message({
        type: 'error',
        message: '上传失败',
      })

      this.isUploading = false
    },
    // 预览
    handlePictureCardPreview(file) {
      this.dialogImageUrl = file.url
      this.dialogVisible = true
    },
    // 对象转成指定字符串分隔
    listToString(list, separator) {
      let strs = ''
      separator = separator || ','
      for (let i in list) {
        strs += list[i].url.replace(this.baseUrl, '') + separator
      }
      return strs != '' ? strs.substr(0, strs.length - 1) : ''
    },
    handleOnProgress(event, file, fileList) {
      this.isUploading = true
    },
  },
}
</script>

<style scoped lang="scss">
::v-deep .el-upload--picture-card {
  border-radius: 2px;
}

// .el-upload--picture-card 控制加号部分
::v-deep.hide .el-upload--picture-card {
  display: none;
}
// 去掉动画效果
::v-deep .el-list-enter-active,
::v-deep .el-list-leave-active {
  transition: all 0s;
}

::v-deep .el-list-enter,
.el-list-leave-active {
  opacity: 0;
  transform: translateY(0);
}
::v-deep .el-upload-list--picture-card .el-upload-list__item-thumbnail {
  object-fit: contain;
}

// 角标颜色
::v-deep .el-upload-list--picture-card .el-upload-list__item-status-label {
  background-color: #18a8dc;
}

// 已上传图片
::v-deep .el-upload-list {
  line-height: 1;
  .el-upload-list__item {
    margin: 0 16px 16px 0;
    width: 104px;
    height: 104px;
    border: 1px solid #e5eaec;
    border-radius: 2px;

    .el-progress {
      width: 102px !important;
      .el-progress-circle {
        width: 102px !important;
        height: 102px !important;
      }
    }
  }
}

// 上传按钮
::v-deep .el-upload {
  position: relative;
  width: 104px;
  height: 104px;
  line-height: 1;
  background: #f7f8fb;

  .el-icon-plus {
    margin-top: 29px;
    margin-bottom: 8px;
    font-size: 16px;
  }

  .photo-text {
    margin: 0;
    font-weight: 400;
    font-size: 14px;
    line-height: 22px;
    text-align: center;
    color: #adb1b3;
  }
}

// 预览
::v-deep .dialog-preview {
  overflow: hidden;

  .el-dialog__header {
    position: relative;
    padding: 11px 24px !important;
    z-index: 2;
    background: #f8faff;
    border-radius: 4px 4px 0 0;
    text-align: left;

    .header {
      display: flex;
      align-items: center;
      font-size: 14px;
      height: 22px;
      line-height: 22px;
      color: #00244d;
      font-weight: bold;
    }

    .el-dialog__headerbtn {
      top: 15px;
      right: 24px;
    }
  }

  .el-dialog__body {
    padding: 24px;
    overflow-y: auto;

    img {
      display: block;
      max-width: 100%;
      margin: 0 auto;
    }
  }
}
</style>