VB.NET
* Imports System.Runtime.InteropServices

Public Class Form1

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

End Sub

Private Sub CheckBox1_CheckedChanged(sender As Object, e As EventArgs) Handles CheckBox1.CheckedChanged
If CheckBox1.Checked Then
Win32.AllocConsole()
Console.WriteLine("Done!")
Else
Win32.FreeConsole()
End If
End Sub
End Class
Public Class Win32
<DllImport("kernel32.dll")> Public Shared Function AllocConsole() As Boolean

End Function
<DllImport("kernel32.dll")> Public Shared Function FreeConsole() As Boolean

End Function

End Class