按鈕靠右對齊

 

<div class="row">
   <div class="col-md-6">
      <div class="dropdown">
        <button aria-expanded="false" aria-haspopup="true" class="btn btn-secondary dropdown-toggle" data-toggle="dropdown" id="dropdownMenuButton" type="button">
          Dropdown button
        </button>
        <div aria-labelledby="dropdownMenuButton" class="dropdown-menu">
          <a class="dropdown-item" href="#">Action</a>
          <a class="dropdown-item" href="#">Another action</a>
          <a class="dropdown-item" href="#">Something else here</a>
        </div>
      </div>
    </div>
    <div class="col-md-6">
        <div class="text-right">
                <button class="btn btn-default" type="button">Default</button>
        </div>    
    </div>
  </div>