gistfile1.txt

public static class ControlExtensions
{
    public static void Invoke(this Control control, MethodInvoker method)
    {
        if (control.InvokeRequired == false)
        {
            // The executing thread _is_ the thread that owns the control's underlying
            // handle and as such, there is no need to marshall the method invocation.
            method.Invoke();
        }
        else
        {
            control.Invoke(method);
        }
    }

    public static void BeginInvoke(this Control control, MethodInvoker method)
    {
        if (control.InvokeRequired == false)
        {
            // The executing thread _is_ the thread that owns the control's underlying
            // handle and as such, there is no need to marshall the method invocation.
            method.Invoke();
        }
        else
        {
            control.BeginInvoke(method);
        }
    }
}