Assembly: System.Web (in system.web.dll)
The XmlDataSource control can present its underlying data in both tabular and hierarchical format to Web server controls that bind to it. Controls such as GridView or DropDownList use the XmlDataSource to bind to XML data and present it in list or tabular form, while controls that derive from the HierarchicalDataBoundControl class, such as TreeView, bind to XML data and present it in hierarchical form.
The XmlDataSource creates each view type internally through different code paths. If the GetView method is called on the XmlDataSource control, an XmlDataSourceView object is created by the XmlDataSource control. If the GetHierarchicalView method is called, an XmlHierarchicalDataSourceView object is created. The XmlDataSourceView class is provided for Web server controls that derive from DataBoundControl and bind to lists and tabular data, while the XmlHierarchicalDataSourceView is provided for Web server controls that derive from HierarchicalDataBoundControl and bind to hierarchical data. Internally, the DataBoundControl and CompositeDataBoundControl classes call the Select method of XmlDataSourceView object view to retrieve data from a data source, while a class derived from HierarchicalDataBoundControl calls the Select method.
Like all HierarchicalDataSourceView helper objects, the XmlHierarchicalDataSourceView defines the operations that the data source can perform with the underlying data. Because the XmlHierarchicalDataSourceView class only overrides the Select method, the associated XmlDataSource control does not support sort expressions or execute, delete, or update operations.