Module Demo

'------------------------------------------------------------------------------------------
'           Notice of My Copyright and Intellectual Property Rights
'
' Any intellectual property contained within the program by Joseph L. Bolen remains the
' intellectual property of the Joseph L. Bolen. This means that no person may distribute,
' publish or provide such intellectual property to any other person or entity for any
' reason, commercial or otherwise, without the express written permission of Joseph L. Bolen.
'
'                 Copyright © 2014. All rights reserved.
'        All trademarks remain the property of their respective owners.
'-------------------------------------------------------------------------------------------
' Program Name:   Module Demo
' Author:         Joseph L. Bolen
' Date Created:   Oct 2014
'
' Description:    Demonstration of the use of a Module for publicly accessed shared methods
'                 and variables.
'
'                 Documentation is at:
'                   App's screen image is at: http://imgur.com/4xd73rA
'                   App's Visual Basic .NET code is at http://pastebin.com/vHfvzAjB
'                   Video tutorial at YouTube: http://www.youtube.com/user/bolenpresents
'
'-------------------------------------------------------------------------------------------

Option Strict On

Public Class MainForm

#Region " Form Events"

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

        'FriendValueLabel.Text = GlobalMethods.globalFriendVar
        FriendValueLabel.Text = globalFriendVar
        PublicValueLabel.Text = globalPublicVar
    End Sub

#End Region

#Region " Control Events"

    ' Process and calculate the sum of two numbers.
    Private Sub SumButton_Click(sender As Object, e As EventArgs) _
        Handles SumButton.Click

        Dim firstValue As Double = CDbl(FirstTextBox.Text)
        Dim secondtValue As Double = CDbl(SecondTextBox.Text)

        'SumValueLabel.Text = PlainAddFunction(firstValue, secondtValue).ToString
        'SumValueLabel.Text = FriendAddFunction(firstValue, secondtValue).ToString
        SumValueLabel.Text = PublicAddFunction(firstValue, secondtValue).ToString
    End Sub

#End Region

End Class

'====================================================================================
' Module GlobalMethods
'====================================================================================
Module GlobalMethods

#Region " Global Variables"

    ' globalPrivateVar is not accessible to other classes
    Private globalPrivateVar As String = "Private"

    ' globalFriendVar is accessible to other classes
    Friend globalFriendVar As String = "Friend"

    ' globalPublicVar is accessible to other classes.
    Public globalPublicVar As String = "Public"

#End Region

#Region " Global Methods"

    ' While not declared as such, this is a Public function.
    Function PlainAddFunction(ByVal value1 As Double, ByVal value2 As Double) As Double
        Return value1 + value2
    End Function

    ' Explicitly declared Private function, is not accessible outside Module.
    Private Function PrivateAddFunction(ByVal value1 As Double, ByVal value2 As Double) As Double
        Return value1 + value2
    End Function

    ' Explicitly declared Friend function.
    Friend Function FriendAddFunction(ByVal value1 As Double, ByVal value2 As Double) As Double
        Return value1 + value2
    End Function

    ' Explicitly declared Public function.
    Public Function PublicAddFunction(ByVal value1 As Double, ByVal value2 As Double) As Double
        Return value1 + value2
    End Function

#End Region

End Module