iteration

I'm stumped here. I've got a user control with one to infinity minus 1 instances of another user control in it. at some points, I need to call the same method on those controls (ex. user presses the clear button on the big control, I want to call the clear f(x) on each of the controls) I...

Does anyone know how to do a single tread iteration. For example I have the following array: ("dog", "cat", "mouse", "bird") I need to go through the array in such a way that it picks up each object once through the first run and then return to the beginning again and pick up the first two...