energy_app/src/views/facilityManage/common-vue/uploader.vue

<template>
  <!-- :after-read="afterRead"  -->
  <!-- :after-read="afterRead" -->
  <van-uploader
    v-model="fileList"
    :disabled="disableImg"
    multiple
    :deletable="deletable"
    :max-count="1"
    :afterRead="afterRead"
    :before-delete="delImg"
    @click-upload="onUpload"
    accept="image/*"
  >
    <div class="uploader" >
      <van-icon name="plus" class="uploader-icon" />
    </div>
  </van-uploader>
</template>

<script>
import { uploadFile } from '@/api/api.js'
import { chooseAlbumAndTakePhoto } from '@/utils/dsbridge'
import { getImageBlobUrl } from '@/utils/index'
export default {
  props: {
    type: {
      type: String,
      default: '',
    },
    value: {
      type: Array,
      default: () => [],
    },
    deletable: {
      type: Boolean,
      default: true,
    },
  },

  data() {
    return {
      disableImg: false,
      fileList: [],
    }
  },
  watch: {
    // 父组件异步回填(如历史记录 getHistory 晚于 mounted)时同步列表;
    // 上传后父组件把 value 改写为 [url字符串] 时不覆盖本地回显
    value: {
      handler(val) {
        if (val && val.length && val.every(item => typeof item === 'object')) {
          this.fileList = val.map(item => ({ ...item, isImage: true }))
        }
      },
      immediate: true,
      deep: true,
    },
  },
  beforeDestroy() {
    this.fileList = []
  },
  methods: {
    base64ToFile(data, fileName) {
      const dataArr = data.split(',')
      const byteString = window.atob(dataArr[1])
      const options = {
        type: 'image/jpeg',
        endings: 'native',
      }
      const u8Arr = new Uint8Array(byteString.length)
      for (let i = 0; i < byteString.length; i++) {
        u8Arr[i] = byteString.charCodeAt(i)
      }
      let formData = new FormData()
      let fileOfBlob = new File([u8Arr], fileName + '.jpg', options) //返回文件流
      formData.append('file', fileOfBlob)
      return formData
    },
    // 上传图片调用原生的方法 获取到绝对路径调用getImageFileFromUrl
    onUpload() {
      console.log('--------chooseAlbumAndTakePhoto---', 'onUpload')
      chooseAlbumAndTakePhoto(async (data) => {
        console.log('--------onUpload---', data)
        let d = 'data:image/jpeg;base64,' + data
        this.fileIamge = d
        let params = this.base64ToFile(d, new Date().getTime().toString())
        console.log('--------params---', params)
        const res = await uploadFile(params)
        console.log('--------res---', res)
        if (res.code == 0) {
          const blobUrl = await getImageBlobUrl(res.data.attach_id)
          console.log('--------回显 blobUrl---', blobUrl)
          if (!blobUrl) return
          this.fileList.push({
            fileName: res.data.original_name,
            fileId: res.data.attach_id,
            url: blobUrl,
            isImage: true,
          })
          this.$emit('onUpload', this.fileList, this.type)
        }
      })
    },
    async afterRead(file) {
      console.log('--------afterRead---', file)
      this.disableImg = true
      let params = new FormData()
      params.append('file', file.file)
      console.log(file.file)
      console.log(params)
      // console.log(decryptParseToJSON(a),77777777);
      const res = await uploadFile(params)
      if (res.code == 0) {
        this.disableImg = false
        this.$emit('afterRead', res.data, this.type)
      }else{
        this.disableImg = false
      }
      return true
    },
    beforeRead(file) {
      if (file.size > 30000) {
        return this.compressFiles(file)
      } else {
        return file
      }
    }, //压缩图片
    compressFiles(fileObj) {
      let type = fileObj.type
      return new Promise((resolve, reject) => {
        let reader = new FileReader()
        reader.readAsDataURL(fileObj)
        reader.onload = function (e) {
          let image = new Image() //新建一个img标签（不嵌入DOM节点，仅做canvas操作)
          image.src = e.target.result //让该标签加载base64格式的原图
          image.onload = function () {
            //图片加载完毕后再通过canvas压缩图片，否则图片还没加载完就压缩，结果图片是全黑的
            let canvas = document.createElement('canvas'), //创建一个canvas元素
              context = canvas.getContext('2d'), //context相当于画笔，里面有各种可以进行绘图的API
              imageWidth = image.width / 2, //压缩后图片的宽度，这里设置为缩小一半
              imageHeight = image.height / 2, //压缩后图片的高度，这里设置为缩小一半
              data = '' //存储压缩后的图片
            canvas.width = imageWidth //设置绘图的宽度
            canvas.height = imageHeight //设置绘图的高度

            //使用drawImage重新设置img标签中的图片大小，实现压缩。drawImage方法的参数可以自行查阅W3C
            context.drawImage(image, 0, 0, imageWidth, imageHeight)
            //使用toDataURL将canvas上的图片转换为base64格式
            data = canvas.toDataURL(type)
            canvas.toBlob(function (blob) {
              const f = new File([blob], fileObj.name, { type })
              resolve(f)
            }, type)
          }
        }
      })
    },
    delImg(file, detail) {
      this.fileList.splice(detail.index, 1)
      this.$emit('delImg', file, detail, this.type)
    },

    checkImgisUpload(list) {
      if (this.fileList && list && this.fileList.length == list.length) {
        return false
      } else {
        return true
      }
    },
  },
}
</script>
<style lang='less' scoped>
/deep/ .van-uploader__preview-image {
  padding: 10px;
  box-sizing: border-box;
  background: #fff;
  box-shadow: 0 2px 12px 0 rgba(0, 0, 0, 0.1);
  border-radius: 10px;
  margin-left: 20px;
  margin-top: 10px;
}

/deep/ .van-uploader__preview-delete {
  margin-top: 10px;
}

.uploader {
  width: 2.133333rem;
  height: 2.133333rem;
  background: #f7f7f7;
  border-radius: 5px;
  display: flex;
  justify-content: center;
  align-items: center;
  margin: 10px 0 10px 20px;
  .uploader-icon {
    font-size: 30px;
    color: #ababab;
  }
}
</style>