Dictionary(TKey, TValue).KeyCollection Class (System.Collections.Generic)

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Microsoft Visual Studio 2008/.NET Framework 3.5

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.NET Framework Class Library

Dictionary<(Of <(TKey, TValue>)>)..::.KeyCollection Class

Represents the collection of keys in a Dictionary<(Of <(TKey, TValue>)>). This class cannot be inherited.

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

Syntax

Visual Basic (Declaration)

<SerializableAttribute> _
Public NotInheritable Class KeyCollection _
    Implements ICollection(Of TKey), IEnumerable(Of TKey),  _
    ICollection, IEnumerable

Visual Basic (Usage)

Dim instance As Dictionary.KeyCollection

[SerializableAttribute]
public sealed class KeyCollection : ICollection<TKey>, 
    IEnumerable<TKey>, ICollection, IEnumerable

Visual C++

[SerializableAttribute]
public ref class KeyCollection sealed : ICollection<TKey>, 
    IEnumerable<TKey>, ICollection, IEnumerable

JScript

public final class KeyCollection implements ICollection<TKey>, IEnumerable<TKey>, ICollection, IEnumerable

Remarks

The Dictionary<(Of <(TKey, TValue>)>)..::.Keys property returns an instance of this type, containing all the keys in that Dictionary<(Of <(TKey, TValue>)>). The order of the keys in the Dictionary<(Of <(TKey, TValue>)>)..::.KeyCollection is unspecified, but it is the same order as the associated values in the Dictionary<(Of <(TKey, TValue>)>)..::.ValueCollection returned by the Dictionary<(Of <(TKey, TValue>)>)..::.Values property.

The Dictionary<(Of <(TKey, TValue>)>)..::.KeyCollection is not a static copy; instead, the Dictionary<(Of <(TKey, TValue>)>)..::.KeyCollection refers back to the keys in the original Dictionary<(Of <(TKey, TValue>)>). Therefore, changes to the Dictionary<(Of <(TKey, TValue>)>) continue to be reflected in the Dictionary<(Of <(TKey, TValue>)>)..::.KeyCollection.

Inheritance Hierarchy

System..::.Object
System.Collections.Generic..::.Dictionary<(Of <(TKey, TValue>)>)..::.KeyCollection

Thread Safety

Public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

A Dictionary<(Of <(TKey, TValue>)>)..::.KeyCollection can support multiple readers concurrently, as long as the collection is not modified. Even so, enumerating through a collection is intrinsically not a thread-safe procedure. To guarantee thread safety during enumeration, you can lock the collection during the entire enumeration. To allow the collection to be accessed by multiple threads for reading and writing, you must implement your own synchronization.

Platforms

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Version Information

.NET Framework

Supported in: 3.5, 3.0, 2.0

.NET Compact Framework

Supported in: 3.5, 2.0

XNA Framework

Supported in: 3.0, 2.0, 1.0

Reference

Dictionary<(Of <(TKey, TValue>)>)..::.KeyCollection Members

System.Collections.Generic Namespace