ListItemCollection Class

.NET Framework (current version)

Other Versions

A collection of ListItem objects in a list control. This class cannot be inherited.

Namespace: System.Web.UI.WebControls
Assembly: System.Web (in System.Web.dll)

Inheritance Hierarchy

System::Object
System.Web.UI.WebControls::ListItemCollection

Syntax

C++

public ref class ListItemCollection sealed : ICollection, IEnumerable, 
	IList, IStateManager

Constructors

	Name	Description
	ListItemCollection()	Initializes a new instance of the ListItemCollection class.

Properties

	Name	Description
	Capacity	Gets or sets the maximum number of items that the ListItemCollection can store.
	Count	Gets the number of ListItem objects in the collection.
	IsReadOnly	Gets a value indicating whether the ListItemCollection is read-only.
	IsSynchronized	Gets a value indicating whether access to the ListItemCollection is synchronized (thread-safe).
	Item[Int32]	Gets a ListItem at the specified index in the collection.
	SyncRoot	Gets the object that can be used to synchronize access to the ListItemCollection.

Methods

	Name	Description
	Add(ListItem^)	Appends the specified ListItem to the end of the collection.
	Add(String^)	Appends a ListItem to the end of the collection that represents the specified string.
	AddRange(array<ListItem^>^)	Adds the items in an array of ListItem objects to the collection.
	Clear()	Removes all ListItem objects from the collection.
	Contains(ListItem^)	Determines whether the collection contains the specified item.
	CopyTo(Array^, Int32)	Copies the items from the ListItemCollection to the specified System::Array, starting with the specified index.
	Equals(Object^)	Determines whether the specified object is equal to the current object.(Inherited from Object.)
	FindByText(String^)	Searches the collection for a ListItem with a Text property that equals the specified text.
	FindByValue(String^)	Searches the collection for a ListItem with a Value property that contains the specified value.
	GetEnumerator()	Returns a System.Collections::IEnumerator implemented object that contains all ListItem objects in the ListItemCollection.
	GetHashCode()	Serves as the default hash function. (Inherited from Object.)
	GetType()	Gets the Type of the current instance.(Inherited from Object.)
	IndexOf(ListItem^)	Determines the index value that represents the position of the specified ListItem in the collection.
	Insert(Int32, ListItem^)	Inserts the specified ListItem in the collection at the specified index location.
	Insert(Int32, String^)	Inserts a ListItem which represents the specified string in the collection at the specified index location.
	Remove(ListItem^)	Removes the specified ListItem from the collection.
	Remove(String^)	Removes a ListItem from the collection that represents the specified string.
	RemoveAt(Int32)	Removes the ListItem at the specified index from the collection.
	ToString()	Returns a string that represents the current object.(Inherited from Object.)

Explicit Interface Implementations

	Name	Description
	IList::Add(Object^)	This API supports the product infrastructure and is not intended to be used directly from your code. For a description of this member, see Add.
	IList::Contains(Object^)	This API supports the product infrastructure and is not intended to be used directly from your code. For a description of this member, see Contains.
	IList::IndexOf(Object^)	This API supports the product infrastructure and is not intended to be used directly from your code. For a description of this member, see IndexOf.
	IList::Insert(Int32, Object^)	This API supports the product infrastructure and is not intended to be used directly from your code. For a description of this member, see Insert.
	IList::Remove(Object^)	This API supports the product infrastructure and is not intended to be used directly from your code. For a description of this member, see Remove.
	IStateManager::LoadViewState(Object^)	This API supports the product infrastructure and is not intended to be used directly from your code. Loads the previously saved state.
	IStateManager::SaveViewState()	This API supports the product infrastructure and is not intended to be used directly from your code. Returns object containing state changes.
	IStateManager::TrackViewState()	This API supports the product infrastructure and is not intended to be used directly from your code. Starts tracking state of changes.
	IList::IsFixedSize	This API supports the product infrastructure and is not intended to be used directly from your code. For a description of this member, see IsFixedSize.
	IList::Item[Int32]	This API supports the product infrastructure and is not intended to be used directly from your code. For a description of this member, see Item.
	IStateManager::IsTrackingViewState	This API supports the product infrastructure and is not intended to be used directly from your code. For a description of this member, see IsTrackingViewState.

Extension Methods

	Name	Description
	AsParallel()	Overloaded. Enables parallelization of a query.(Defined by ParallelEnumerable.)
	AsQueryable()	Overloaded. Converts an IEnumerable to an IQueryable.(Defined by Queryable.)
	Cast<TResult>()	Casts the elements of an IEnumerable to the specified type.(Defined by Enumerable.)
	OfType<TResult>()	Filters the elements of an IEnumerable based on a specified type.(Defined by Enumerable.)

The ListItemCollection class represents a collection of ListItem objects. The ListItem objects, in turn, represent the items displayed in list controls, such as the ListBox. To programmatically retrieve ListItem objects from a list control, use one of following methods:

Use the indexer to get a single ListItem from the collection, using array notation.
Use the CopyTo method to copy the contents of the collection to a System::Array object, which can then be used to get items from the collection.
Use the GetEnumerator method to create a System.Collections::IEnumerator implemented object, which can then be used to get items from the collection.
Use foreach (C#) or For Each (Visual Basic) to iterate through the collection.

The Count property specifies the total number of items in the collection, and is commonly used to determine the upper bound of the collection. You can add and remove items from the collection by using the Add and Remove methods.

Examples

The following code example demonstrates creating ListItemCollection objects, adding items to the collections, and removing items from the collections. In the example, the ListItemCollection named listBoxData is used as the data source for a ListBox control called ListBox1, and the ListItemCollection called ddBoxData is used as the data source for a DropDownList control called DropDownList1.