代码如下
因为文档还没加载，就读了js，js就不起作用了想在head里用的话，用
意思是等文档已经加载完成了之后再执行 js 代码
或者把代码放在body里面也可
修改后的代码如下
jQuery放到head中失效的原因与解决方法
2019年8月12日
Bonky Zhu
If someone is able to show me that what I think or do is not right, I will happily change, for I seek the truth, by which no one was ever truly harmed. It is the person who continues in his self-deception and ignorance who is harmed.
