BootStrap3中模态对话框的使用

<div class="modal fade" id="edit">
    <div class="modal-dialog ">
      <div class="modal-content">
        <div class="modal-header">
<h3 class="modal-title">头标题</h3>   
            <a class="close" data-dismiss="modal">
              <span>关闭</span>
            </a>
        </div>
        <div class="modal-body">
          内容
        </div>
        <div class="modal-footer">
  <!--脚-->
          <a class="btn btn-default " data-dismiss="modal">关闭</a>
        </div>
      </div>
    </div>
  </div>