VB.Net/Language Basics/For Each

Материал из VB Эксперт
Версия от 15:42, 26 мая 2010; Admin (обсуждение | вклад) (1 версия)
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Exit a For Each loop

<source lang="vbnet"> Imports System Imports System.Collections Public Class MainClass

   Shared Sub Main(ByVal args As String())
       Dim employees As New Collection
       employees.Add(New Employee("A"))
       employees.Add(New Manager("B"))
       employees.Add(New Employee("C"))
       Dim a_manager As Manager = Nothing
       For Each emp2 As Employee In employees
           If TypeOf emp2 Is Manager Then
               a_manager = CType(emp2, Manager)
               Exit For
           End If
       Next emp2
       Console.WriteLine("Manager: " & a_manager.Name)
   End Sub

End Class

Public Class Employee

   Public Name As String
   Public Sub New(ByVal new_name As String)
       Name = new_name
   End Sub
   Public Overridable Function IsManager() As Boolean
       Return False
   End Function

End Class Public Class Customer

   Public Name As String
   Public Sub New(ByVal new_name As String)
       Name = new_name
   End Sub

End Class Public Class Manager

   Inherits Employee
   Public Sub New(ByVal new_name As String)
       MyBase.new(new_name)
   End Sub
   Public Overrides Function IsManager() As Boolean
       Return True
   End Function

End Class

      </source>


Loop through an Array

<source lang="vbnet"> Imports System Public Class MainClass

   Shared Sub Main()
       "Declare an array
       Dim strFriends(4) As String
       "Populate the array
       strFriends(0) = "R"
       strFriends(1) = "B"
       strFriends(2) = "S"
       strFriends(3) = "S"
       strFriends(4) = "K"
       "Enumerate the array
       For Each strName As String In strFriends
           "Add the array item to the list
           System.Console.WriteLine(strName)
       Next
   End Sub

End Class

      </source>


Use For Each to Loop an Array

<source lang="vbnet"> Imports System Public Class MainClass

   Shared Sub Main(ByVal args As String())
       Dim friends() As String = {"A", "B", "C","D", "E"}
       Dim friendName As String
       For Each friendName In friends
           Console.WriteLine(friendName)
       Next
   End Sub
   

End Class

      </source>