最近在给客户开发一个CRM系统，其中用到了BOOTSTRAP的模态框。版本是3。由于是刚开始用该框架。所以在正式部署到项目中前，需要测试一下，找到框架中的如下部分。需要说明的是。我用的asp.net mvc框架开发。测试也是在asp.net  mvc环境下。

 复制版本3中的代码如下：

<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#exampleModal" data-whatever="@mdo">Open modal for @mdo</button>
<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#exampleModal" data-whatever="@fat">Open modal for @fat</button>
<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#exampleModal" data-whatever="@getbootstrap">Open modal for @getbootstrap</button>
...more buttons...<div class="modal fade" id="exampleModal" tabindex="-1" role="dialog" aria-labelledby="exampleModalLabel"><div class="modal-dialog" role="document"><div class="modal-content"><div class="modal-header"><button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button><h4 class="modal-title" id="exampleModalLabel">New message</h4></div><div class="modal-body"><form><div class="form-group"><label for="recipient-name" class="control-label">Recipient:</label><input type="text" class="form-control" id="recipient-name"></div><div class="form-group"><label for="message-text" class="control-label">Message:</label><textarea class="form-control" id="message-text"></textarea></div></form></div><div class="modal-footer"><button type="button" class="btn btn-default" data-dismiss="modal">Close</button><button type="button" class="btn btn-primary">Send message</button></div></div></div>
</div>

上述代码经过改造，放在自己的mvc环境中：

    <button type="button" class="btn btn-primary" data-toggle="modal" data-target="#exampleModal" data-whatever="s">Open modal for s</button><div class="modal fade" id="exampleModal" tabindex="-1" role="dialog" aria-labelledby="exampleModalLabel"><div class="modal-dialog" role="document"><div class="modal-content"><div class="modal-header"><button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true">&times;</span></button><h4 class="modal-title" id="exampleModalLabel">New message</h4></div><div class="modal-body"><form><div class="form-group"><label for="recipient-name" class="control-label">Recipient:</label><input type="text" class="form-control" id="recipient-name"></div><div class="form-group"><label for="message-text" class="control-label">Message:</label><textarea class="form-control" id="message-text"></textarea></div></form></div><div class="modal-footer"><button type="button" class="btn btn-default" data-dismiss="modal">Close</button><button type="button" class="btn btn-primary">Send message</button></div></div></div></div>
</div>

 运行，结果没法弹出模态框。后仔细查找发现问题出在button的代码上面：

    <button type="button" class="btn btn-primary" data-toggle="modal" data-target="#exampleModal" data-whatever="s">Open modal for s</button>

发现该代码是bootstrap 3版本的写法，遂换成如下bootstrap 5的写法：

<button type="button" class="btn btn-primary" data-bs-toggle="modal" data-bs-target="#exampleModal" data-whatever="hello">Open modal for hello</button>

然后OK!