Vue + Element UI with preview PDF before upload file

Question

I am using Vue and element UI to achieve the upload file function, also use pdfvuer node module. In this case, the files will upload to Amazon S3 finally.

I want to preview the file before the user click confirms button. ref picture: upload

Currently, I used the blob and createObjectUrl method to realize preview PNG and JPG type files. but not work with PDF type ref picture: upload and preview png

Here is my code with upload of dialog:

HTML :

      <span class="pt-0">
        <p class="text-center mt-0">Please selecct file which you want to import</p>
        <el-upload
          accept="image/png, image/jpeg, application/pdf"
          class="avatar-uploader"
          :show-file-list="true"
          :before-upload="beforeAvatarUpload"
          action=""
        >
          <i class="fas fa-cloud-upload-alt fa-2x my-8" v-if="objectURL == ''"></i>


          <img :src="objectURL" width="100%" />
          <pdf :src="imageUrl.webkitRelativePath" />


          <div class="el-upload__text" v-if="objectURL == ''">Click here to execute</div>
          <div class="el-upload__tip" slot="tip">
            You can just upload PDF/PNG/JPG file only
          </div>
        </el-upload>
      </span>
      <span slot="footer" class="dialog-footer">
        <el-button @click="innerDialogUploadFile = false">Cancel</el-button>
        <el-button type="danger" @click="handleUploadFile">Confirm</el-button>
      </span>
    </el-dialog>

JS :

data(){ retrun ... }
methods:{
   beforeAvatarUpload(file) {
      this.objectURL = window.URL.createObjectURL(new Blob([file]));
      this.imageUrl = window.URL.createObjectURL(new Blob([file]));
      const isJPG = file.type === "image/jpeg";
      const isPNG = file.type === "image/png";
      const isPDF = file.type === "application/pdf";
      const isLt2M = file.size / 1024 / 1024 < 20;
      switch (file.type) {
        case "image/png":
          this.fileType = 1;
          break;
        case "image/jpeg":
          this.fileType = 2;
          break;
        case "application/pdf":
          this.fileType = 3;
          break;
        default:
          break;
      }
      return isJPG && isPNG && isPDF && isLt2M;
    },
}

Can someone help me to resolve this issue? Either offer me another way to re-write code.

If it needs more detailed information on my code, please let me know.

Answer 1

Updated. I finally found out the solution to my question. I just use the <embed> tag to reach the preview function.

Here is my code :

<input @change="handleChange" />

// preview area
<embed
    v-if="embedSrc"
    type="video/webm"
    :src="embedSrc"
    width="100%"
    style="max-height: 50rem; min-height: 20rem"
/>

...
data:{
  return {
    embedSrc: ''
  }
}
...
methods:{
   handleChange(){
      this.embedSrc = URL.createObjectURL(event.target.files[0]);
   }
}

Please note that add : before src, either it can't get dynamic src correctly.