From hamsandwich.inc:
PHP Code:
/**
* Hooks the virtual table for the specified entity's class.
* An example would be: RegisterHam(Ham_TakeDamage, id, "player_hurt");
* Look at the Ham enum for parameter lists.
* Note: This will cause hooks for the entire internal class that the entity is
* not exclusively for the provided entity.
*
* @param function The function to hook.
* @param EntityId The entity classname to hook.
* @param callback The forward to call.
* @param post Whether or not to forward this in post.
* @return Returns a handle to the forward. Use EnableHamForward/DisableHamForward to toggle the forward on or off.
*/
native HamHook:RegisterHamFromEntity(Ham:function, EntityId, const Callback[], Post=0);
So, it does make more sense to use RegisterHam() if you already know your entities classname.