Nullable.GetUnderlyingType Method (System)

' This code example demonstrates the 
' Nullable.GetUnderlyingType() method.

Imports System
Imports System.Reflection

Class Sample
    ' Declare a type named Example. 
    ' The MyMethod member of Example returns a Nullable of Int32.

    Public Class Example
        Public Function MyMethod() As Nullable(Of Integer)
            Return 0
        End Function
    End Class 'Example

' 
'   Use reflection to obtain a Type object for the Example type.
'   Use the Type object to obtain a MethodInfo object for the MyMethod method.
'   Use the MethodInfo object to obtain the type of the return value of 
'     MyMethod, which is Nullable of Int32.
'   Use the GetUnderlyingType method to obtain the type argument of the 
'     return value type, which is Int32.
'
    Public Shared Sub Main() 
        Dim t As Type = GetType(Example)
        Dim mi As MethodInfo = t.GetMethod("MyMethod")
        Dim retval As Type = mi.ReturnType
        Console.WriteLine("Return value type ... {0}", retval)
        Dim answer As Type = Nullable.GetUnderlyingType(retval)
        Console.WriteLine("Underlying type ..... {0}", answer)

    End Sub 'Main
End Class 'Sample
'
'This code example produces the following results:
'
'Return value type ... System.Nullable`1[System.Int32]
'Underlying type ..... System.Int32
'

// This code example demonstrates the 
// Nullable.GetUnderlyingType() method.

using System;
using System.Reflection;

class Sample 
{
// Declare a type named Example. 
// The MyMethod member of Example returns a Nullable of Int32.

    public class Example
    {
        public int? MyMethod() 
        {
        return 0;
        }
    }

/* 
   Use reflection to obtain a Type object for the Example type.
   Use the Type object to obtain a MethodInfo object for the MyMethod method.
   Use the MethodInfo object to obtain the type of the return value of 
     MyMethod, which is Nullable of Int32.
   Use the GetUnderlyingType method to obtain the type argument of the 
     return value type, which is Int32.
*/   
    public static void Main() 
    {
        Type t = typeof(Example);
        MethodInfo mi = t.GetMethod("MyMethod");
        Type retval = mi.ReturnType;
        Console.WriteLine("Return value type ... {0}", retval);
        Type answer = Nullable.GetUnderlyingType(retval);
        Console.WriteLine("Underlying type ..... {0}", answer);
    }
}
/*
This code example produces the following results:

Return value type ... System.Nullable`1[System.Int32]
Underlying type ..... System.Int32

*/