Question

My application runs some threads and every thread does something.
I want that each thread shows its status in a list box.

So, how a thread can identify itself (by using thread ID or something else) and set its status into a List?

Answer 1

Every thread has an id. You can access it with

Thread t;
int id = t.ManagedThreadId;

To update a global datastructure with some state i would use a dictionary and use the id as the key. Be aware of locking the access of that data structure:

Dictionary<int, SomeStateClass> threadStates = new Dictionary<int, SomeStateClass>();

public void updateThreadState(int id, SomeStateClass newState) {
    lock (threadStates) {
        threadStates[id] = newState;
    }
}