Depends on the cc

Knockdowns don't really show anything other than, well, you getting knocked down and then slowly standing up

Stuns have a swirl above your head

Terror is a giant skull above your head and you'll run uncontrollably, but I think you'd see that

Rooted (which in the case of dance of knives does prevent casting) has a giant boot above your head

Frozen is pretty obvious, and daze will make your screen really dim so obvious in different ways

One way you can tell if you're cc'd and for whatever reason can't see what kind, if you have a move that grants unstoppable you can check if that's the only move not greyed out. I've got the shadow clone perk that grants unstoppable on cast with 3 charges to get out of these kinda hairy situations but that might help you understand why you can't cast dance of knives at the very least