VB.Net/Class/Shared

Class Shared Variable

Imports System
Public Class MainClass
    Shared Sub Main(ByVal args As String())
      Console.WriteLine("Students before instantiation: " & Student.Count)
      Dim student1 As Student = New Student("A", "B")
      Dim student2 As Student = New Student("C", "D")
      " output of student2 after instantiation
      Console.WriteLine("Students after instantiation: " & vbCrLf & _
         "via Student.Count: " & Student.Count)
      " display name of first and second student
      Console.WriteLine(vbCrLf & "Students 1: " & _
         student1.FirstName & " " & student1.LastName & _
         vbCrLf & "Student 2: " & student2.FirstName & " " & _
         student2.LastName)
      " mark student1 and student2 for garbage collection
      student1 = Nothing
      student2 = Nothing
      System.GC.Collect() " request garbage collection
      
    End Sub
End Class
" Class Student uses Shared variable.
Class Student
   Inherits Object
   Private mFirstName As String
   Private mLastName As String
   " number of objects in memory
   Private Shared mCount As Integer
   " Student constructor
   Public Sub New(ByVal firstNameValue As String, _
      ByVal lastNameValue As String)
      mFirstName = firstNameValue
      mLastName = lastNameValue
      mCount += 1 " increment shared count of students
      Console.WriteLine _
         ("Student object constructor: " & mFirstName & _
         " " & mLastName)
   End Sub " New
   " finalizer method decrements Shared count of students
   Protected Overrides Sub Finalize()
      mCount -= 1 " decrement mCount, resulting in one fewer object
      Console.WriteLine _
         ("Student object finalizer: " & mFirstName & _
         " " & mLastName & "; count = " & mCount)
   End Sub " Finalize
   " return first name
   Public ReadOnly Property FirstName() As String
      Get
         Return mFirstName
      End Get
   End Property " FirstName
   " return last name
   Public ReadOnly Property LastName() As String
      Get
         Return mLastName
      End Get
   End Property " LastName
   " property Count
   Public Shared ReadOnly Property Count() As Integer
      Get
         Return mCount
      End Get
   End Property " Count
End Class " Student

Class with all shared Member variables

Imports System.IO
Module Module1
    Sub Main()
        Console.WriteLine("Today: " & Today.TodayDate)
        Console.WriteLine("Day: " & Today.Day)
        Console.WriteLine("Month: " & Today.Month)
        Console.WriteLine("Year: " & Today.Year)
        Console.WriteLine("Day of week: " & Today.NumericDayOfWeek)
        Console.WriteLine("Day of week: " & Today.StringDayOfWeek)
    End Sub
End Module
    Class Today
        Public Shared TodayDate As DateTime = Now()
        Public Shared Day As Integer = Now.Day()
        Public Shared Month As Integer = Now.Month()
        Public Shared Year As Integer = Now.Year()
        Public Shared NumericDayOfWeek As Integer = Now.DayOfWeek()
        Public Shared StringDayOfWeek As String = Now.DayOfWeek.ToString()
    End Class

Shared Method Demo

Imports System
public class MainClass
   Shared Sub Main()
        Dim c1 As New C()
        Dim c2 As New C()
        c2.Test()
        c.SharedTest()
   End Sub
End Class
Class C
    Public Shared Sub SharedTest()
        Static x As Integer
        x = x + 1
        console.WriteLine(x)
    End Sub
    Public Sub Test()
        Static x As Integer
        x = x + 1
        console.WriteLine(x)
    End Sub
End Class

User Shared variable to count instance number

Imports System.IO
Module Module1
    Sub Main()
        Dim p As New Professor()
        Console.WriteLine("count {0}", p.Count)
        Dim pp As New Professor()
        Console.WriteLine("count {0}", pp.Count)
    End Sub
End Module
    Class Professor
        Public Shared Count As Integer = 0
        Public Name As String
        Private Age As Integer
        Public OfficeNumber As String
        Private HomePhone As String
        Public Sub New()
            Count = Count + 1
        End Sub
        
    End Class

Use Shared method to construct Object

Imports System
Imports System.Drawing
Imports System.Data
Imports System.IO
Imports System.Collections
Imports System.Windows.Forms
Imports System.Drawing.Printing
Public Class MainClass
    Shared Sub Main()
       Dim newUser As User
       newUser = User.CreateUser("Joe", "password15")
       Console.WriteLine(newUser.Username)
    End Sub
End Class

Public Class User
    Public Username As String
    Private password As String

    Public Shared Function CreateUser(ByVal username As String, _
                     ByVal password As String) As User
        Dim user As New User()
        user.Username = username
        user.Password = password
        Return user
    End Function
End Class