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Nullable.Equals Method (Object)

Note: This method is new in the .NET Framework version 2.0.

Indicates whether the current Nullable object is equal to a specified object.

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

'Declaration
Public Overrides Function Equals ( _
	other As Object _
) As Boolean
'Usage
Dim instance As Nullable(Of T)
Dim other As Object
Dim returnValue As Boolean

returnValue = instance.Equals(other)
public boolean Equals (
	Object other
)
public override function Equals (
	other : Object
) : boolean

Parameters

other

An object.

Return Value

true if the other parameter is equal to the current Nullable object; otherwise, false. This table describes how equality is defined for the compared values:

Return Value

Description

true

The HasValue property is false, and the other parameter is a null reference (Nothing in Visual Basic). That is, two null values are equal by definition.

-or-

The HasValue property is true, and the value returned by the Value property is equal to the other parameter.

false

The HasValue property for the current Nullable structure is true, and the other parameter is a null reference (Nothing in Visual Basic).

-or-

The HasValue property for the current Nullable structure is false, and the other parameter is not a null reference (Nothing in Visual Basic).

-or-

The HasValue property for the current Nullable structure is true, and the value returned by the Value property is not equal to the other parameter.

If the HasValue property of the current Nullable structure is true, equality is determined by passing the other parameter to the Equals method of the underlying value of the current Nullable structure.

The following code example determines whether an object and a Nullable object are equal to the current Nullable object.

' This code example demonstrates the Nullable(Of T).Equals 
' methods.

Imports System

Class Sample
    Public Shared Sub Main() 
        Dim nullInt1 As Nullable(Of Integer) = 100 
        Dim nullInt2 As Nullable(Of Integer) = 200
        Dim myObj As Object
        
    ' Determine if two nullable of System.Int32 values are equal. 
    ' The nullable objects have different values.
        Console.Write("1) nullInt1 and nullInt2 ")
        If nullInt1.Equals(nullInt2) Then
            Console.Write("are")
        Else
            Console.Write("are not")
        End If
        Console.WriteLine(" equal.")
        
    ' Determine if a nullable of System.Int32 and an object 
    ' are equal. The object contains the boxed value of the
    ' nullable object.
        myObj = CType(nullInt1, Object)
        Console.Write("2) nullInt1 and myObj ")
        If nullInt1.Equals(myObj) Then
            Console.Write("are")
        Else
            Console.Write("are not")
        End If
        Console.WriteLine(" equal.")
    End Sub 'Main 
End Class 'Sample

'
'This code example produces the following results:
'
'1) nullInt1 and nullInt2 are not equal.
'2) nullInt1 and myObj are equal.
'

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

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

.NET Framework

Supported in: 2.0

.NET Compact Framework

Supported in: 2.0

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