This page demonstrates the Copy to clipboard plug-in.
This dynamic action plug-in can be used to copy the content of an Apex item to the clipboard. In version 1.1 the content of hidden Apex items can also be copied and JQuery selectors are also supported.
The plug-in that can be downloaded from the plug-ins section of apex.world
The plug-in function both for Apex 5.0 and 5.1.

More information is found on this blogpost.

You can use see the plug-in in action by clicking on the buttons. You can paste the result in the textarea in the bottom.