System.Windows.Forms.Control.FindControlBackward C# (CSharp) Method

		private static Control FindControlBackward(Control container, Control start) {

			Control found = null;

			if (start == null) {
				found = FindFlatBackward(container, start);
			}
			else if (start != container) {
				if (start.parent != null) {
					found = FindFlatBackward(start.parent, start);

					if (found == null) {
						if (start.parent != container)
							return start.parent;
						return null;
					}
				}
			}
		
			if (found == null || start.parent == null)
				found = start;

			while (found != null && (found == container || (!((found is IContainerControl) && found.GetStyle(ControlStyles.ContainerControl))) &&
				found.child_controls != null && found.child_controls.Count > 0)) {
//				while (ctl.child_controls != null && ctl.child_controls.Count > 0 && 
//					(ctl == this || (!((ctl is IContainerControl) && ctl.GetStyle(ControlStyles.ContainerControl))))) {
				found = FindFlatBackward(found, null);
			}

			return found;

/*
			Control found;

			found = null;

			if (start != null) {
				found = FindFlatBackward(start.parent, start);
				if (found == null) {
					if (start.parent != container) {
						return start.parent;
					}
				}
			}
			if (found == null) {
				found = FindFlatBackward(container, start);
			}

			if (container != start) {
				while ((found != null) && (!found.Contains(start)) && found.child_controls != null && found.child_controls.Count > 0 && !(found is IContainerControl)) {// || found.GetStyle(ControlStyles.ContainerControl))) {
					found = FindControlBackward(found, null);
					 if (found != null) {
						return found;
					}
				}
			}
			return found;
*/			
		}