上传文件格式校验

<a-upload slot="extra"

    name="file"

    :multiple="true"

    :showUploadList="false"

    :beforeUpload="beforeUpload"

    :customRequest="uploadFile">

    <a href="javascript:;">上传文件</a>

</a-upload>

beforeUpload(file) {       
     var FileExt = file.name.replace(/.+\./, "");       
      if (['jpg','png','txt','zip', 'rar','pdf','doc','docx','xlsx'].indexOf(FileExt.toLowerCase()) === -1){            
          this.$message({ 
              type: 'warning', 
              message: '请上传后缀名为jpg、png、txt、pdf、doc、docx、xlsx、zip或rar的附件！' 
         });                
         return false;       
      }      
}