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Файл:Объектно-ориентированное программирование на языке Visual Basic 2008 в среде разработки Microsoft Visual Studio 2008 и .NET Framework. Часть 2. Учебно
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distance
Public Class LateBinding1
Public Function distance(ByVal x As Single, ByVal y As Single, ByVal z As Single) As Double
Return Math.Sqrt(x ^ 2 + y ^ 2 + z ^ 2)
End Function
End Class
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LateBinding1 obj :
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
Handles Button1.Click
Dim obj As New LateBinding1
MsgBox(obj.distance(5, 5, 10))
End Sub
End Class
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Option Strict Off
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _
Handles Button1.Click
Dim obj As Object = New LateBinding1
MsgBox(obj.distance(5, 5, 10))
End Sub
End Class
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Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles Button1.Click
Dim obj As New LateBinding1
Showdistance(obj)
End Sub
Private Sub Showdistance(ByVal obj As Object)
MsgBox(obj.distance(5, 5, 10))
End Sub
Showdistance
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Public Class Poly
Implements IShared
Public Function distance(ByVal x As Single, ByVal y As Single) As Single Implements _
IShared.SharedDistance
Return CSng(x + y)
End Function
End Class
Public Class Polymorphism
Implements IShared
Public Function distance(ByVal x As Single, ByVal y As Single) As Single Implements _
IShared.SharedDistance
Return CSng(Math.Sqrt(x ^ 2 + y ^ 2))
End Function
End Class
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Interface.vb
Module Interface
End Module
Public Interface IShared
Function SharedDistance(ByVal x As Single, ByVal y As Single) As Single
End Interface
IShared
SharedDistance distance Poly Polymorphism, , distance
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Form1 Button :
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles Button1.Click
Dim obj As New Poly
Showdistance(obj)
End Sub
55
Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs)
Handles Button2.Click
Dim obj As New Polymorphism
Showdistance(obj)
End Sub
Private Sub Showdistance(ByVal obj As Object)
Dim x, y As Single
x = CSng(InputBox(" x"))
y = CSng(InputBox(" y"))
MsgBox(obj.distance(x, y))
End Sub
End Class
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