IHierarchicalEnumerable Interface
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Represents a hierarchical collection that can be enumerated with an IEnumerator interface. Collections that implement the IHierarchicalEnumerable interface are used by ASP.NET site navigation and data source controls.
public interface class IHierarchicalEnumerable : System::Collections::IEnumerable
public interface IHierarchicalEnumerable : System.Collections.IEnumerable
type IHierarchicalEnumerable = interface
interface IEnumerable
Public Interface IHierarchicalEnumerable
Implements IEnumerable
- Derived
- Implements
Examples
The following code example demonstrates how to implement the IHierarchicalEnumerable interface with a class that extends ArrayList and provides a collection of IHierarchyData objects that wrap FileSystemInfo objects. The IHierarchicalEnumerable collection is used by classes that derive from HierarchicalDataSourceView to return a collection of hierarchical nodes when the Select method is called. This code example is part of a larger example provided for the HierarchicalDataSourceControl class.
// A collection of FileSystemHierarchyData objects
public class FileSystemHierarchicalEnumerable :
ArrayList, IHierarchicalEnumerable
{
public FileSystemHierarchicalEnumerable()
: base()
{
}
public IHierarchyData GetHierarchyData(object enumeratedItem)
{
return enumeratedItem as IHierarchyData;
}
}
Public Class FileSystemHierarchicalEnumerable
Inherits ArrayList
Implements IHierarchicalEnumerable
Public Sub New()
End Sub
Public Overridable Function GetHierarchyData( _
ByVal enumeratedItem As Object) As IHierarchyData _
Implements IHierarchicalEnumerable.GetHierarchyData
Return CType(enumeratedItem, IHierarchyData)
End Function
End Class
Remarks
The IHierarchicalEnumerable interface extends the IEnumerable interface and exposes GetHierarchyData, which is a method used to retrieve an IHierarchyData object from an enumerated item, in addition to the GetEnumerator method.
Typically, clients that use IHierarchicalEnumerable collections retrieve an IEnumerator object by calling the GetEnumerator method, then iterate through the enumeration and call the GetHierarchyData on each enumerated item to retrieve an IHierarchyData object.
Methods
GetEnumerator() |
Returns an enumerator that iterates through a collection. (Inherited from IEnumerable) |
GetHierarchyData(Object) |
Returns a hierarchical data item for the specified enumerated item. |
Extension Methods
Cast<TResult>(IEnumerable) |
Casts the elements of an IEnumerable to the specified type. |
OfType<TResult>(IEnumerable) |
Filters the elements of an IEnumerable based on a specified type. |
AsParallel(IEnumerable) |
Enables parallelization of a query. |
AsQueryable(IEnumerable) |
Converts an IEnumerable to an IQueryable. |
Applies to
See also
Atsauksmes
https://aka.ms/ContentUserFeedback.
Drīzumā: 2024. gada laikā mēs pakāpeniski pārtrauksim izmantot “GitHub problēmas” kā atsauksmju par saturu mehānismu un aizstāsim to ar jaunu atsauksmju sistēmu. Papildinformāciju skatiet:Iesniegt un skatīt atsauksmes par