EqualityComparer(T) Class (System.Collections.Generic)

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Microsoft Visual Studio 2008/.NET Framework 3.5

Other versions are also available for the following:

.NET Framework Class Library

EqualityComparer<(Of <(T>)>) Class

Provides a base class for implementations of the IEqualityComparer<(Of <(T>)>) generic interface.

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

Syntax

Visual Basic (Declaration)

<SerializableAttribute> _
Public MustInherit Class EqualityComparer(Of T) _
    Implements IEqualityComparer, IEqualityComparer(Of T)

Visual Basic (Usage)

Dim instance As EqualityComparer(Of T)

[SerializableAttribute]
public abstract class EqualityComparer<T> : IEqualityComparer, 
    IEqualityComparer<T>

Visual C++

[SerializableAttribute]
generic<typename T>
public ref class EqualityComparer abstract : IEqualityComparer, 
    IEqualityComparer<T>

JScript

JScript does not support generic types or methods.

Type Parameters

T: The type of objects to compare.

Remarks

Derive from this class to provide a custom implementation of the IEqualityComparer<(Of <(T>)>) generic interface for use with collection classes such as the Dictionary<(Of <(TKey, TValue>)>) generic class, or with methods such as List<(Of <(T>)>)..::.Sort.

The Default property checks whether type T implements the System..::.IEquatable<(Of <(T>)>) generic interface and if so returns an EqualityComparer<(Of <(T>)>) that uses that implementation. Otherwise it returns an EqualityComparer<(Of <(T>)>) that uses the overrides of Object..::.Equals and Object..::.GetHashCode provided by T.

Inheritance Hierarchy

System..::.Object
System.Collections.Generic..::.EqualityComparer<(Of <(T>)>)

Thread Safety

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

Platforms

Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, 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

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.

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