ICollection Interface

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Defines size, enumerators, and synchronization methods for all nongeneric collections.

Namespace:  System.Collections
Assembly:  mscorlib (in mscorlib.dll)

Syntax

'Declaration
<ComVisibleAttribute(True)> _
Public Interface ICollection _
    Inherits IEnumerable

[ComVisibleAttribute(true)]
public interface ICollection : IEnumerable

The ICollection type exposes the following members.

Properties

	Name	Description
	Count	Gets the number of elements contained in the ICollection.
	IsSynchronized	Gets a value indicating whether access to the ICollection is synchronized (thread safe).
	SyncRoot	Gets an object that can be used to synchronize access to the ICollection.

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Methods

	Name	Description
	CopyTo	Copies the elements of the ICollection to an Array, starting at a particular Array index.
	GetEnumerator	Returns an enumerator that iterates through a collection. (Inherited from IEnumerable.)

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Extension Methods

	Name	Description
	AsQueryable	Converts an IEnumerable to an IQueryable. (Defined by Queryable.)
	Cast<TResult>	Converts 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.)

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Remarks

The ICollection interface is the base interface for classes in the System.Collections namespace.

The ICollection interface extends IEnumerable; IDictionary and IList are more specialized interfaces that extend ICollection. An IDictionary implementation is a collection of key/value pairs. An IList implementation is a collection of values and its members can be accessed by index.

If neither the IDictionary interface nor the IList interface meet the requirements of the required collection, derive the new collection class from the ICollection interface instead for more flexibility.

For the generic version of this interface, see System.Collections.Generic.ICollection<T>.

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

See Also

Reference

System.Collections Namespace

IDictionary

IList

System.Collections.Generic.ICollection<T>