VB.Net Tutorial/Class Module/Overloaded functions — различия между версиями

Материал из VB Эксперт
Перейти к: навигация, поиск
м (1 версия)
 
м (1 версия)
 
(нет различий)

Текущая версия на 12:55, 26 мая 2010

Inheritance and overloads

Public Class Tester
    Public Shared Sub Main
        Dim objBob As New Bob
        objBob.Walk("Now I"m walking...")
    End Sub
End Class
Public Class Person
    Public Sub Walk()
        Console.WriteLine("Walking...")
    End Sub
End Class
Class Bob
    Inherits Person
    Public Overloads Sub Walk(ByVal Text As String)
        Console.WriteLine(Text)
    End Sub
End Class
Now I"m walking...

Method Overloads with different number of parameters

Public Class Tester
    Public Shared Sub Main
        Dim Alerter As New MyMessageBox
        
        Alerter.Alert("No Problems!")
        Alerter.Alert("No Problems!", MsgBoxStyle.Exclamation)
    End Sub
End Class

Public Class MyMessageBox
    Public Sub Alert(ByVal Text As String)
        MsgBox(Text)
    End Sub
    Public Sub Alert(ByVal Text As String, ByVal Icon As MsgBoxStyle)
        MsgBox(Text, Icon)
    End Sub
End Class

Overloads function

public class Test
   public Shared Sub Main
        Console.WriteLine(Min(10.1, 10))
        Console.WriteLine(Min("last", "first"))
        Console.WriteLine(Min(#1/1/2000#, #3/4/2000#))
   End Sub
    Overloads Shared Function Min(ByVal dblA As Double, ByVal dblB As Double) As Double
        Min = IIf(dblA < dblB, dblA, dblB)
    End Function
    Overloads Shared Function Min(ByVal strA As String, ByVal strB As String) As String
        Min = IIf(strA < strB, strA, strB)
    End Function
    Overloads Shared Function Min(ByVal dteA As Date, ByVal dteB As Date) As Date
        Min = IIf(dteA < dteB, dteA, dteB)
    End Function

End class
10
first
01/01/2000 12:00:00 AM

Using overloaded methods

Public Class Tester
   Public Shared Sub Main
      Console.WriteLine("The square of Integer 7 is " & _
         Square(7) & vbCrLf & "The square of Double " & _
         "7.5 is " & Square(7.5))

   End Sub 
   
   Shared Function Square(ByVal value As Integer) As Integer
      Return Convert.ToInt32(value ^ 2)
   End Function " Square
   Shared Function Square(ByVal value As Double) As Double
      Return value ^ 2
   End Function " Square
End Class
The square of Integer 7 is 49
The square of Double 7.5 is 56.25

Using overloaded methods to print arrays of different types

Module Test
   Sub Main()
      Dim integerArray As Integer() = {1, 2, 3, 4, 5, 6}
      Dim doubleArray As Double() = {1.1, 2.2, 3.3, 4.4, 5.5, 6.6, 7.7}
      Dim charArray As Char() = {"H"c, "E"c, "L"c, "L"c, "O"c}
      PrintArray(integerArray)
      PrintArray(doubleArray)
      PrintArray(charArray) 
   End Sub " Main
   Sub PrintArray(ByVal inputArray() As Integer)
      For Each element As Integer In inputArray
         Console.Write(element.ToString() & " ")
      Next element
      Console.WriteLine(vbCrLf)
   End Sub 
   
   Sub PrintArray(ByVal inputArray() As Double)
      For Each element As Double In inputArray
         Console.Write(element.ToString() & " ")
      Next element
      Console.WriteLine(vbCrLf)
   End Sub
   
   Sub PrintArray(ByVal inputArray() As Char)
      For Each element As Char In inputArray
         Console.Write(element.ToString() & " ")
      Next element
      Console.WriteLine(vbCrLf)
   End Sub 
End Module
1 2 3 4 5 6
1.1 2.2 3.3 4.4 5.5 6.6 7.7
H E L L O