VB.Net/Class/Property

Class Property Get and Set

 
Imports System
Public Class MainClass
    Shared Sub Main(ByVal args As String())
      Dim time As New CTime3()
      " invoke time6 methods
      time.Second = (time.Second + 1)
      time.Minute = (time.Minute + 1)
      time.Hour = (time.Hour + 1)
      
      Console.WriteLine(  "Hour: " & time.Hour & "; Minute: " & _
         time.Minute & "; Second: " & time.Second )
    End Sub
End Class

" Represents time in 24-hour format and contains properties.
Class CTime3
   Inherits Object
   " declare Integers for hour, minute and second
   Private mHour As Integer
   Private mMinute As Integer
   Private mSecond As Integer
   " CTime3 constructor: initialize each instance variable to zero
   " and ensure that each CTime3 object starts in consistent state
   Public Sub New()
      SetTime(0, 0, 0)
   End Sub " New
   " CTime3 constructor: 
   " hour supplied, minute and second defaulted to 0
   Public Sub New(ByVal hourValue As Integer)
      SetTime(hourValue, 0, 0)
   End Sub " New
   " CTime3 constructor: 
   " hour and minute supplied; second defaulted to 0
   Public Sub New(ByVal hourValue As Integer, _
      ByVal minuteValue As Integer)
      SetTime(hourValue, minuteValue, 0)
   End Sub " New
   " CTime3 constructor: hour, minute and second supplied
   Public Sub New(ByVal hourValue As Integer, _
      ByVal minuteValue As Integer, ByVal secondValue As Integer)
      SetTime(hourValue, minuteValue, secondValue)
   End Sub " New
   " CTime3 constructor: another CTime3 object supplied
   Public Sub New(ByVal timeValue As CTime3)
      SetTime(timeValue.mHour, timeValue.mMinute, _
         timeValue.mSecond)
   End Sub " New
   " set new time value using universal time;
   " uses properties to perform validity checks on data
   Public Sub SetTime(ByVal hourValue As Integer, _
      ByVal minuteValue As Integer, ByVal secondValue As Integer)
      Hour = hourValue     " looks
      Minute = minuteValue " dangerous
      Second = secondValue " but it is correct
   End Sub " SetTime
   " property Hour
   Public Property Hour() As Integer
      " return mHour value
      Get
         Return mHour
      End Get
      " set mHour value
      Set(ByVal value As Integer)
         If (value >= 0 AndAlso value < 24) Then
            mHour = value
         Else
            mHour = 0
         End If
      End Set
   End Property " Hour
   " property Minute
   Public Property Minute() As Integer
      " return mMinute value
      Get
         Return mMinute
      End Get
      " set mMinute value
      Set(ByVal value As Integer)
         If (value >= 0 AndAlso value < 60) Then
            mMinute = value
         Else
            mMinute = 0
         End If
      End Set
   End Property " Minute
   " property Second
   Public Property Second() As Integer
      " return mSecond value
      Get
         Return mSecond
      End Get
      " set mSecond value
      Set(ByVal value As Integer)
         If (value >= 0 AndAlso value < 60) Then
            mSecond = value
         Else
            mSecond = 0
         End If
      End Set
   End Property " Second
End Class

Compare int property

  
Imports System.Collections.Generic
Public Class Car
  Public PetName As String = String.Empty
  Public Color As String = String.Empty
  Public Speed As Integer
  Public Make As String = String.Empty
  Public Overloads Overrides Function ToString() As String
    Return String.Format("Make={0}, Color={1}, Speed={2}, PetName={3}", _
      Make, Color, Speed, PetName)
  End Function
End Class
Module Program

  Sub Main()
        Dim myCars As New List(Of Car)(New Car() { _
    New Car With {.PetName = "D", .Color = "Silver", .Speed = 100, .Make = "BMW"}, _
    New Car With {.PetName = "C", .Color = "Tan", .Speed = 90, .Make = "BMW"}, _
    New Car With {.PetName = "B", .Color = "Rust", .Speed = 5, .Make = "Yugo"}, _
    New Car With {.PetName = "A", .Color = "White", .Speed = 43, .Make = "Ford"}})
    Dim fastCars = From c In myCars Where c.Speed > 55 Select c
    For Each car In fastCars
      Console.WriteLine(car.PetName)
    Next
  End Sub
End Module

Declare Protected Properties

 
Imports System
Imports System.Collections
Imports System.Data
Imports System.IO
Imports System.Xml.Serialization
Imports System.Windows.Forms
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.Drawing.Text
Imports System.Drawing.Printing

Public Class MainClass
    Shared Sub Main()
        Dim e As New Programmer("Joe", 15)
        e.RaiseSalary(0.1D)
        "Console.WriteLine(e.TheName & " salary is now " & e.Salary())
        " Compile Error
    End Sub
End Class

Public Class Employee
    Private m_Name As String
    Private m_Salary As Decimal
    Public Sub New(ByVal theName As String, ByVal curSalary As Decimal)
        m_Name = theName
        m_Salary = curSalary
    End Sub
    Public ReadOnly Property TheName() As String
        Get
            Return m_Name
        End Get
    End Property
    Protected ReadOnly Property Salary() As Decimal
        Get
            Return MyClass.m_Salary
        End Get
    End Property
    Public Overridable Overloads Sub RaiseSalary(ByVal Percent As Decimal)
         m_Salary = (1 + Percent) * m_Salary
    End Sub
End Class
Public Class Programmer
    Inherits Employee
    Public Sub New(ByVal theName As String, ByVal curSalary As Decimal)
        MyBase.New(theName, curSalary)
    End Sub
    Public Overloads Overrides Sub RaiseSalary(ByVal Percent As Decimal)
        MyBase.RaiseSalary(1.2D * Percent)
    End Sub
End Class

Define and use Class: Property

 
Imports System
Imports System.Collections
Imports System.ruponentModel
Imports System.Windows.Forms
Imports System.Data
Imports System.Configuration
Imports System.Resources
Imports System.Drawing
Imports System.Drawing.Drawing2D
Imports System.IO
Imports System.Drawing.Printing

Public Class MainClass
    Shared Sub Main()
        Dim objCar As New Car
        "Set the Color property to Red
        objCar.Color = "Red"
        "Show what the value of the property is
        Console.WriteLine("My car is this color:")
        Console.WriteLine(objCar.Color)

        "Report the speed
        Console.WriteLine("The car"s speed is:")
        Console.WriteLine(objCar.Speed)
        "Accelerate
        objCar.Accelerate(5)
        "Report the new speed
        Console.WriteLine("The car"s speed is now:")
        Console.WriteLine(objCar.Speed)

        "Report the number of doors
        Console.WriteLine("The number of doors is:")
        Console.WriteLine(objCar.NumberOfDoors)
        "Try changing the number of doors to 1000
        objCar.NumberOfDoors = 1000
        "Report the number of doors
        Console.WriteLine("The number of doors is:")
        Console.WriteLine(objCar.NumberOfDoors)
        "Now try changing the number of doors to 2
        objCar.NumberOfDoors = 2
        "Report the number of doors
        Console.WriteLine("The number of doors is:")
        Console.WriteLine(objCar.NumberOfDoors)

        "Accelerate the car to 25mph
        objCar.Accelerate(25)
        "Report whether or not the car is moving
        If objCar.IsMoving = True Then
            Console.WriteLine("The car is moving.")
        Else
            Console.WriteLine("The car is stopped.")
        End If
    End Sub

End Class

    Public Class Car
        Implements IDisposable
        Public Color As String
        Public HorsePower As Integer
        Private _speed As Integer
        Private _numberOfDoors As Integer
        Public ReadOnly Property Speed() As Integer
            Get
                Return _speed
            End Get
        End Property
        Public Sub Accelerate(ByVal accelerateBy As Integer)
            "Adjust the speed
            _speed += accelerateBy
        End Sub
        Public Property NumberOfDoors() As Integer
            Get
                Return _numberOfDoors
            End Get
            Set(ByVal value As Integer)
                "Is the new value between two and five
                If value >= 2 And value <= 5 Then
                    _numberOfDoors = value
                End If
            End Set
        End Property
        Public Function IsMoving() As Boolean
            "Is the car"s speed zero?
            If Speed = 0 Then
                Return False
            Else
                Return True
            End If
        End Function
        "Constructor
        Public Sub New()
            "Set the default values
            Color = "White"
            _speed = 0
            _numberOfDoors = 5
        End Sub
        Public Overridable Function CalculateAccelerationRate() As Double
            Return 4.2
        End Function
        Private disposed As Boolean = False
        " IDisposable
        Private Overloads Sub Dispose(ByVal disposing As Boolean)
            If Not Me.disposed Then
                If disposing Then
                    " TODO: put code to dispose managed resources
                End If
                " TODO: put code to free unmanaged resources here
            End If
            Me.disposed = True
        End Sub
#Region " IDisposable Support "
        " This code added by Visual Basic to correctly implement the disposable pattern.
        Public Overloads Sub Dispose() Implements IDisposable.Dispose
            " Do not change this code.  Put cleanup code in Dispose(ByVal disposing As Boolean) above.
            Dispose(True)
            GC.SuppressFinalize(Me)
        End Sub
        Protected Overrides Sub Finalize()
            " Do not change this code.  Put cleanup code in Dispose(ByVal disposing As Boolean) above.
            Dispose(False)
            MyBase.Finalize()
        End Sub
#End Region
    End Class

Get and set Properties

 
Imports System.IO
Module Module1
    Sub Main()
        Dim Palm As New Book("Book 1", "Author 1")
        Dim Upgrading As New Book("Book 2", "Author 2")
        Palm.Price = 49.99
        Palm.Pages = 2000
        Upgrading.Price = 119.99
        Upgrading.Pages = 600
        Console.WriteLine(Upgrading.Pages)
    End Sub
End Module
    Class Book
        Public Title As String
        Public Author As String
        Private BookPrice As Double
        Private BookPages As Integer
        Public Property Price() As Double
            Get
                Return BookPrice
            End Get
            Set(ByVal Value As Double)
                If (Value >= 0) And (Value <= 100) Then
                    BookPrice = Value
                Else
                    Console.WriteLine("Invalid price for " & Title)
                    BookPrice = 0
                End If
            End Set
        End Property
        Public Property Pages() As Integer
            Get
                Return BookPages
            End Get
            Set(ByVal Value As Integer)
                If (Value >= 0) And (Value <= 1500) Then
                    BookPages = Value
                Else
                    Console.WriteLine("Invalid page count for " & Title)
                    BookPages = 0
                End If
            End Set
        End Property
        Public Sub New(ByVal Title As String, ByVal Author As String)
            Me.Title = Title
            Me.Author = Author
        End Sub
    End Class

Property Shadow during Inheritance

 
Imports System
Imports System.Diagnostics
Public Class MainClass
    Shared Sub Main()
        Dim mgr As New Manager
        mgr.LastName = "Manager Last Name"
        mgr.EmployeeId = 1
        Dim emp As Employee = CType(mgr, Employee)
        emp.LastName = "Employee Last Name"
        emp.EmployeeId = 2
        Dim per As Person = CType(mgr, Person)
        per.LastName = "Person Last Name"
        per.EmployeeId = "A"
        
        Console.WriteLine(mgr.EmployeeId & ": " & mgr.LastName)
        Console.WriteLine(emp.EmployeeId & ": " & emp.LastName)
        Console.WriteLine(per.EmployeeId & ": " & per.LastName)
    End Sub
End Class
Public Class Person
    Public LastName As String
    Public EmployeeId As String
End Class
Public Class Employee
    Inherits Person
    Public Shadows EmployeeId As Long
End Class
Public Class Manager
    Inherits Employee
    Public Shadows LastName As String
End Class

Shared Property Demo

 
Imports System
Public Class MainClass
  Shared Sub Main()
        Dim e As New Employee("Joe", 100000)
        Console.WriteLine(e.TheName & " is employee# " & e.EmployeeId & "  with salary " & e.Salary())
        Dim Sally As New Employee("Sally", 150000)
        Console.WriteLine(Sally.TheName & " is employee# " & _
        Sally.EmployeeId & " with salary " & Sally.Salary())
        Console.WriteLine("Please press the Enter key")
  End Sub

End Class

Public Class Employee
    Private m_Name As String
    Private m_Salary As Decimal
    Private Shared m_EmployeeID As Integer = 10000
    Private m_MyID As Integer
  Public Sub New(ByVal thesName As String, ByVal curSalary As Decimal)
        m_Name = thesName
        m_Salary = curSalary
        m_EmployeeID = m_EmployeeID + 1
        m_MyID = m_EmployeeID
  End Sub
  ReadOnly Property EmployeeId() As Integer
    Get
            Return m_MyID
    End Get
  End Property
  ReadOnly Property TheName() As String
    Get
      TheName = m_Name
    End Get
  End Property
  ReadOnly Property Salary() As Decimal
    Get
      Salary = m_Salary
    End Get
  End Property
End Class