Use the RemoveAt method to remove the TreeNodeStyle object at the specified zero-based index location from a TreeNodeStyleCollection object. All the items that are located after the removed node are then moved up one level to fill the vacant position in the tree structure. The indexes of the moved items are also updated.
As an alternative, you can remove a specific TreeNodeStyle object by using the Remove method. You can also remove every node in the collection by using the Clear method.
Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)