写项目时表单中同时用到了bootstrap的datetimepicker插件和jquery的验证表单插件，但是发现这两个在同时使用时datetimepicker插件会失效，浏览器控制台显示$().datetimepicker is not a function，引入的cdn都没错，最后发现是要把validate的cdn放在datetimepicker的前面，两个插件才能都生效。而且datetimepicker的js代码必须写在文件尾部。不知道是什么原因，有大神看见请帮我解答一下。
附上引用cdn：
<!--validate验证表单插件-->
<script src="http://static.runoob.com/assets/jquery-validation-1.14.0/lib/jquery.js"></script>
<script src="http://static.runoob.com/assets/jquery-validation-1.14.0/dist/jquery.validate.min.js"></script>
<script src="http://static.runoob.com/assets/jquery-validation-1.14.0/dist/localization/messages_zh.js"></script>
<script src="https://cdn.bootcss.com/jquery-validate/1.17.0/additional-methods.js"></script>
<!-- 引入datetimepicker -->
<script src="https://cdn.bootcss.com/moment.js/2.18.1/moment-with-locales.min.js"></script>
<link href="https://cdn.bootcss.com/bootstrap-datetimepicker/4.17.47/css/bootstrap-datetimepicker.min.css" rel="stylesheet">
<script src="https://cdn.bootcss.com/bootstrap-datetimepicker/4.17.47/js/bootstrap-datetimepicker.min.js"></script>