Nullable(Of T).Value Property

Gets the value of the current Nullable(Of T) object if it has been assigned a valid underlying value.

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

'Declaration
Public ReadOnly Property Value As T

Property Value

Type: T
The value of the current Nullable(Of T) object if the HasValue property is true. An exception is thrown if the HasValue property is false.

ExceptionCondition
InvalidOperationException

The HasValue property is false.

If a value of type T has not been assigned to the Nullable(Of T) object, you can compare it to Nothing and retrieve its HasValue property, but you cannot access its Value property or call its other members.

The following example uses the HasValue property of a Nullable<Integer> object to determine whether it should display the object's Value property or its GetValueOrDefault property.

Module Example
   Public Sub Main()
      Dim n1 As New Nullable(Of Integer)(10)
      Dim n2 As Nullable(Of Integer)
      Dim n3 As New Nullable(Of Integer)(20)
      n3 = Nothing 
      Dim items() As Nullable(Of Integer) = { n1, n2, n3 }

      For Each item In items
         Console.WriteLine("Has a value: {0}", item.HasValue)
         If item.HasValue Then
            Console.WriteLine("Type: {0}", item.GetType().Name)
            Console.WriteLine("Value: {0}", item.Value)
         Else
            Console.WriteLine("Null: {0}", item Is Nothing)
            Console.WriteLine("Default Value: {0}", item.GetValueOrDefault())
         End If
         Console.WriteLine()
      Next                   
   End Sub 
End Module 
' The example displays the following output: 
'       Has a value: True 
'       Type: Int32 
'       Value: 10 
'        
'       Has a value: False 
'       Null: True 
'       Default Value: 0 
'        
'       Has a value: False 
'       Null: True 
'       Default Value: 0

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

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