Network Programming in .NET

If you try to update the UI of a windows form app with a thread spun off by the main thread you get an exception, Microsoft’s suggested solution is as follows;
private void SetText(string text)

{
	// InvokeRequired required compares the thread ID of the
	// calling thread to the thread ID of the creating thread.
	// If these threads are different, it returns true.
	if (this.textBox1.InvokeRequired)
	{	
		SetTextCallback d = new SetTextCallback(SetText);
		this.Invoke(d, new object[] { text });
	}
	else
	{
		this.textBox1.Text = text;
	}
}

Which omits the code for the SetTextCallback delegate, which over time, can clutter up your application.

Instead, I would suggest using an Action<T> as follows:

var d = new Action<string>(SetText);