Nullable(Of T).GetValueOrDefault methods. : Nullable « Data Type « VB.Net Tutorial






  1. VB.Net Tutorial
  2. Data Type
  3. Nullable
Imports System

Class Sample
    Public Shared Sub Main() 
        Dim mySingle As Nullable(Of System.Single) = 12.34F 
        Dim yourSingle As Nullable(Of System.Single) = - 1.0F 

        Console.WriteLine(mySingle)
        Console.WriteLine(yourSingle)

        yourSingle = mySingle.GetValueOrDefault()
        Console.WriteLine(mySingle)
        Console.WriteLine(yourSingle)

        mySingle = Nothing
        yourSingle = mySingle.GetValueOrDefault()
        Console.WriteLine(mySingle)
        Console.WriteLine(yourSingle)

        mySingle = 12.34F
        yourSingle = - 1.0F

        Console.WriteLine(mySingle)
        Console.WriteLine(yourSingle)

        yourSingle = mySingle.GetValueOrDefault(- 222.22F)
        Console.WriteLine(mySingle)
        Console.WriteLine(yourSingle)

        mySingle = Nothing
        yourSingle = mySingle.GetValueOrDefault(- 333.33F)
        Console.WriteLine(mySingle)
        Console.WriteLine(yourSingle)

    End Sub


End Class








2.48.Nullable
2.48.1.Assigning Nothing to a variable sets it to the default value for its declared type.
2.48.2.Nullable(Of T).GetValueOrDefault methods.
2.48.3.If the variable is of a reference type, a value of Nothing is a null value.