vscode安装这个，

即会出现提示，

    <div class="alert alert-warning alert-dismissible fade show" role="alert">
      <button type="button" class="close" data-dismiss="alert" aria-label="Close">
        <span aria-hidden="true">&times;</span>
      </button>
      A simple primary alert—check it out!
      <strong>abcd</strong> 
    </div>