In the past two days, I installed the centos system in virtualbox. After the operating system was installed, I found that the clipboard could not be shared, so I installed the enhanced toolkit of virtualbox. Finally, refer to this article on the Internet to get it:
http://jingyan.baidu.com/article/9c69d48f8ec01613c8024e58.html
Note: After adding to the vboxsf user group, you need to switch users or log in again to take effect.