c# - Spawn a new thread to open a new window and close it from a different thread

Question

Right now I have C# code to spawn a new window in a different thread, this works, but as soon as the new spawned window opens, it closes and the thread ends. How would I make it so the new spawned window can be closed from the first thread?

Here is a "tree" of how the spawning currently works:

Main thread
--Uses a function in the main thread to start another function in a separate thread to open w window, causing the window to use that thread.

Basically I just want the two windows to each have their own thread. And be able to control the spawned secondary window from the first window thread.

Answer 1

I bet what you're doing is something like this:

new Thread(() => new TestForm().Show()).Start();

because this makes the window disappear immediately, like you describe.

Try this instead:

 new Thread(() => new TestForm().ShowDialog()).Start();

ShowDialog spins its own message pump, and only returns when the window is closed.