How does switching characters affect how they earn experience?

I'm fairly new to Dungeon Defenders and have realised that having a mix of characters is pretty useful (somewhat unsurprisingly). So, when I'm playing solo I have got in to the habit of switching between the Squire (for building spike walls), Apprentice (for building towers) and Huntress (for the combat).

Given that I'm flitting between these three characters, and am favouring the Huntress most in the combat phase, how is experience doled out between them?

Experience is given to the current active character. This is regardless of who built the traps/towers that you are using. In multi-player games this fact is true as well. Experience is now shared among the team and experience is based on the monster you kill. You'll see how much each monster is worth as they are killed and the message pops up in the bottom right hand corner when they die.

This fact makes it incredibly easy to level a character from 1-70 when you have tower characters that can handle the entire map with just towers. (Hard Glitterhelm is the best for this method).

Not really sure, but from experience, it seems that the experience only goes to the active character.