ElementUI上传组件选取文件按钮禁用

<el-upload
  :disabled="isExamSolt"
  class="upload-demo"
  :action="doUpload"
  :before-upload="beforeUpload"
  :on-change="handleChange"
  ref="newupload"
  multiple
  :limit="1"
  :on-exceed="handleExceed"
  :auto-upload="false">
  <el-button slot="trigger" size="small" :disabled="isExamSolt" type="primary">选取文件</el-button>
  <el-button size="small" type="success" :disabled="isExamTea" @click="submitUpload">上传</el-button>
</el-upload>

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