element 上传文件 upload

<el-dialog
    title="上传文件"
    :visible.sync="upload_dialog"
    :close-on-click-modal="false"
    :close-on-press-escape="false"
    :show-close="false"
    width="500px"
   >
    <el-upload
     class="upload-demo"
     ref="upload"
     drag
     accept=".csv"
     action=""
     :multiple="false"
     :limit="1"
     :auto-upload="false"
     :on-change="handle_csv_change"
    >
     <i class="el-icon-upload"></i>
     <div class="el-upload__text">将文件拖到此处，或<em>点击上传</em></div>
     <div class="el-upload__tip" slot="tip">只能上传.csv文件</div>
    </el-upload>
    <span slot="footer" class="dialog-footer">
     <el-button @click="cancel('upload_csv')">取 消</el-button>
     <el-button type="primary" @click="determine_upload">确 定</el-button>
    </span>
   </el-dialog>