You shouldn't try to do this, let me tell you why. I'm assuming you want to disable ctrl + c because you don't want the user to be able to copy content from your site, well have you thought about the fact that there are a dozen of other ways to copy your content?
- Download html file and copy in their favorite text editor
- Inspect element and copy content from there
- Use mouse to right click -> copy
And for my good friend @glenatron:
- Network sniffer like Fiddler between the browser and the network card
- Screenshots, Taking a photograph of the monitor
... The list goes on and on.
Also, trying to stop users from normal functionality will only bother and annoy them; most likely causing them to leave your site and never return.
与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…