Assembly: System.Web (in System.Web.dll)
If index is -1, style is inserted at the beginning of the SubMenuStyleCollection collection. If index equals the number of items in the collection, style is appended to the end of the SubMenuStyleCollection collection.
The OnValidate method is called to validate the style parameter before it is added to the collection. The OnInsert method is called before the SubMenuStyle object is inserted into the collection, and the OnInsertComplete method is called after the object is inserted.