Sitefinity CMS enables you to create hierarchical data structures using the Module builder. As of Sitefinity CMS version 7.1, you can add complex hierarchies containing multiple child types.

The base class for all dynamic types, created with the Module builder, is DynamicContent. It implements IHierarchicalItem interface. This interface contains properties for accessing parent and child items. A single dynamic content item can have a single parent item and multiple child items from different types. You can access the parent item through SystemParentItem property. SystemParentId property holds the Id of the parent item and you can use it for filtering dynamic items by parent. 

You create hierarchical types using Sitefinity CMS backend.
For more information, see Create a dynamic content type.

Field controls

The backend for hierarchical types uses the same Overview: Field controls as flat types and other content types, such as the built-in News and Events types. In addition, hierarchical types use the ParentSelectorField, which provides the ability to change the parent of the current item.

For each created module, Sitefinity CMS automatically generates useful code samples. To view these code samples, in the backend, click Administration » Module builder » <Module name>. In the right pane, you can see a link to the code reference.