@{
Layout = null;
}
<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width" />
<title>View1</title>
<link href="~/Bootstrap3.3.7/css/bootstrap.min.css" rel="stylesheet" />
<script src="~/jquery3.3.1/jquery-3.3.1.min.js"></script>//注意：jquery版本太低有可能显示不出效果
<script src="~/Bootstrap3.3.7/js/bootstrap.min.js"></script>
</head>
<body>
<!-- Single button -->
<div class="btn-group">
<button type="button" class="btn btn-default dropdown-toggle" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
Action <span class="caret"></span>
</button>
<ul class="dropdown-menu">
<li><a href="#">Action</a></li>
<li><a href="#">Another action</a></li>
<li><a href="#">Something else here</a></li>
<li role="separator" class="divider"></li>
<li><a href="#">Separated link</a></li>
</ul>
</div>
</body>
</html>