Reflection: invoke method on a form using its handle

Question

1. I use the following to invoke a method on a form: private void InvokeMethod(Form form, string methodName, params object[] parms) { try { EventHandler eh = (EventHandler)Delegate.CreateDelegate(typeof (EventHandler), form, methodName); if (eh != null) { form.Invoke(eh, parms); } } catch(Exception ex) { MessageBox.Show(ex.Message); return; } } 2. The prerequisite for #1 is: try { testAssembly = Assembly.LoadFrom(textBox3.Text); Type t = testAssembly.GetType(textBox4.Text); testForm = (Form)testAssembly.CreateInstance(t.FullName); ThreadPool.QueueUserWorkItem(new WaitCallback(RunApp), testForm); } catch(Exception ex) { MessageBox.Show(ex.Message); } 3. What I need is invoking a method on a form that is running, i.e. skipping #2. I thought I could retrieve the handle to the running form, then by some cast invoke the wanted method. However, I am stuck. I have no idea how to go from a form's handle back to the form. 4. Please help.