el-upload的预览功能使用 window.open()

handlePreview1

handlePreview2两种方法 window.open

<el-upload
  class="upload-demo"
  action="https://jsonplaceholder.typicode.com/posts/"
  :on-preview="handlePreview"
  :on-remove="handleRemove"
  :before-remove="beforeRemove"
  multiple
  :limit="3"
  :on-exceed="handleExceed"
  :file-list="fileList">
  <el-button size="small" type="primary">点击上传</el-button>
  <div slot="tip" class="el-upload__tip">只能上传jpg/png文件，且不超过500kb</div>
</el-upload>
<script>
  export default {
    data() {
      return {
        fileList: [{name: 'food.jpeg', url: 'https://fuss10.elemecdn.com/3/63/4e7f3a15429bfda99bce42a18cdd1jpeg.jpeg?imageMogr2/thumbnail/360x360/format/webp/quality/100'}, {name: 'food2.jpeg', url: 'https://fuss10.elemecdn.com/3/63/4e7f3a15429bfda99bce42a18cdd1jpeg.jpeg?imageMogr2/thumbnail/360x360/format/webp/quality/100'}]
      };
    },
    methods: {
      handleRemove(file, fileList) {
        console.log(file, fileList);
      },
      handlePreview1(file) {
        console.log(file);


    let appUrl = ''
        if (process.env.NODE_ENV === 'development') {
          appUrl = `${window.location.protocol}//${window.location.host}`
        } else {
          appUrl = `${window.location.protocol}//${window.location.host}`
        }
        const pdfReg = /^.+(\.pdf)$/
        if (pdfReg.test(file.name)) {
          window.open(
            `${appUrl}/#/previewer?type=doc&fileUrl=` + this.baseDomainUrl + file.url
          )
        } else {
          window.open(
            `${appUrl}/#/previewer?type=img&fileUrl=` + this.baseDomainUrl + file.url
          )
        }


      },

 handlePreview2(item) {
      // 截取返回路径的最后三位，判断文件是图片还是pdf文件，如果是pdf文件添加type为pdf，如果是图片type为image
      const failType = item.attachUrl.substring(item.attachUrl.length - 3);
      let type = "";
      if (failType === "pdf") {
        type = "doc";
      } else {
        type = "img";
      }
      window.open(`/#/previewer?type=${type}&fileUrl=${item.attachUrl}`);
    },
      handleExceed(files, fileList) {
        this.$message.warning(`当前限制选择 3 个文件，本次选择了 ${files.length} 个文件，共选择了 ${files.length + fileList.length} 个文件`);
      },
      beforeRemove(file, fileList) {
        return this.$confirm(`确定移除 ${ file.name }？`);
      }
    }
  }
</script>