wxNodeBase is the node structure used in linked lists (see wxList) and derived classes. You should never use wxNodeBase class directly, however, because it works with untyped (void *) data and this is unsafe. Use wxNodeBase-derived classes which are automatically defined by WX_DECLARE_LIST and WX_DEFINE_LIST macros instead as described in wxList documentation (see example there). Also note that although there is a class called wxNode, it is defined for backwards compatibility only and usage of this class is strongly deprecated.
In the documentation below, the type T should be thought of as a "template'' parameter: this is the type of data stored in the linked list or, in other words, the first argument of WX_DECLARE_LIST macro. Also, wxNode is written as wxNode<T> even though it isn't really a template class -- but it helps to think of it as if it were.
T * GetData() const
Retrieves the client data pointer associated with the node.
wxNode<T> * GetNext() const
Retrieves the next node or NULL if this node is the last one.
wxNode<T> * GetPrevious()
Retrieves the previous node or NULL if this node is the first one in the list.
void SetData(T *data)
Sets the data associated with the node (usually the pointer will have been set when the node was created).
Returns the zero-based index of this node within the list. The return value will be wxNOT_FOUND if the node has not been added to a list yet.