What is the principle of windows replication?

It's not that troublesome. Right-click the text to be copied, and click the shortcut menu to realize it on the menu in the program. Add a menu message mapping function and copy it into the function. For example, on the selected anti-theft clipboard, the function of canceling, clearing, copying, cutting and pasting is provided for the CEdit control CEDIT class for you to copy and paste. Ctrl+c is a shortcut key that can be set directly, but its essence is to call menu functions.