bootstrap如何设置鼠标悬停提示

<button type="button" rel="drevil" data-content="报名截止时间：&#39;+time+&#39;" data-container="body" data-toggle="popover" 
data-placement="bottom"></button>

$(function () { $("[data-toggle='popover']").popover(); });　　　　
　　  $("[rel=drevil]").popover({
                      trigger:'manual',
                      //placement : 'bottom', //placement of the popover. also can use top, bottom, 
                      left or right
                      //天title : &#39;<div style="text-align:center; color:red; text-decoration:underline; 
                      font-size:14px;"> Muah ha ha</div>&#39;, //this is the top title bar of the popover. 
                      add some basic css
                      html: &#39;true&#39;, //needed to show html of course
                      //content : &#39;<div id="popOverBox"><img src="http://www.hd-report.com/wp-content
                      /uploads/2008/08/mr-evil.jpg" width="251" height="201" /></div>&#39;, //this is the 
                      content of the html box. add the image here or anything you want really.
                      animation: false
                  }).on("mouseenter", function () {
                      var _this = this;
                      $(this).popover("show");
                      $(this).siblings(".popover").on("mouseleave", function () {
                          $(_this).popover(&#39;hide&#39;);
                      });
                  }).on("mouseleave", function () {
                      var _this = this;
                      setTimeout(function () {
                          if (!$(".popover:hover").length) {
                              $(_this).popover("hide")
                          }
                      }, 300);
                  });