Bootstrap3下拉菜单的实现

<div class="dropdown"> <button id="dLabel" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">  Dropdown trigger  <span class="caret"></span> </button> <ul class="dropdown-menu" aria-labelledby="dLabel">  ... </ul></div>

$('.dropdown-toggle').dropdown()

$().dropdown('toggle')

$('#myDropdown').on('show.bs.dropdown', function () { // do something…})