Check if nullable is null : nullable « Language Basics « VB.Net

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VB.Net » Language Basics » nullableScreenshots 
Check if nullable is null
   


Option Explicit On
Option Strict On

Class MyClass1
    Public numericValue As Integer?
    Public boolValue As Boolean? = True
    Public Function GetIntFromDatabase() As Integer?
        Return numericValue
    End Function

    Public Function GetBoolFromDatabase() As Boolean?
        Return boolValue
    End Function
End Class

Module Program

    Sub Main()
        Dim dr As New MyClass1()
        Dim As Integer? = dr.GetIntFromDatabase()
        If (i.HasValueThen
            Console.WriteLine("Value of 'i' is: {0}", i.Value)
        Else
            Console.WriteLine("Value of 'i' is undefined.")
        End If
        Dim As Boolean? = dr.GetBoolFromDatabase()
        If (b.HasValueThen
            Console.WriteLine("Value of 'b' is: {0}", b.Value)
        Else
            Console.WriteLine("Value of 'b' is undefined.")
        End If
    End Sub
End Module

   
    
    
  
Related examples in the same category
1.Main with Nullable (Of T)
2.To test nullable type variables for Nothing values, use the Is operator or the IsNot operator.
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