Nullable(Of T).Value Property
[ This article is for Windows Phone 8 developers. If you’re developing for Windows 10, see the latest documentation. ]
Gets the value of the current Nullable(Of T) value.
Assembly: mscorlib (in mscorlib.dll)
| Exception | Condition |
|---|---|
| InvalidOperationException | The HasValue property is false. |
The following code example returns the value of a Nullable(Of T) object if that object has a defined value; otherwise, a default value is returned.
' This code example demonstrates the Nullable(Of T).HasValue ' and Value properties. Class Example Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock) Dim myNow As Nullable(Of DateTime) ' Assign the current date and time to myNow then display its value. myNow = DateTime.Now Display(outputBlock, myNow, "1) ") ' Assign null (Nothing in Visual Basic) to myNow then display its value. myNow = Nothing Display(outputBlock, myNow, "2) ") End Sub 'Main ' Display the date and time. Public Shared Sub Display(ByVal outputBlock As System.Windows.Controls.TextBlock, ByVal displayDateTime As Nullable(Of DateTime), _ ByVal title As String) ' If the HasValue property for the nullable of DateTime input argument is true, ' display the value of the input argument; otherwise, display that no value is ' defined for the input value. outputBlock.Text &= title If displayDateTime.HasValue = True Then outputBlock.Text += String.Format("The date and time is {0:F}.", displayDateTime.Value) & vbCrLf Else outputBlock.Text &= "The date and time is not defined." & vbCrLf End If End Sub 'Display End Class 'Sample ' 'This code example produces the following results: ' '1) The date and time is Tuesday, April 19, 2005 4:16:06 PM. '2) The date and time is not defined. '
Show: