в 16:40, 26 мая 2010

2010-05-26T16:40:30Z

Admin: 1 версия

2010-05-26T12:53:45Z

1 версия

Новая страница

==Extends CollectionBase to create custom Collection==

<source lang="vbnet">Imports System.Collections
Imports System.Collections.Generic
Imports System.Collections.Specialized
public class Test

public Shared Sub Main
Dim emp_list As New EmployeeCollection
emp_list.Add(New Employee("A", "A"))
emp_list.Add(New Employee("B", "B"))
emp_list.Add(New Employee("C", "C"))
emp_list.Add(New Employee("D", "D"))
emp_list.Add(New Employee("E", "E"))
For Each emp As Employee In emp_list
Console.WriteLine(emp.ToString)
Next emp
End Sub

End class
Public Class Employee
Private m_FirstName As String
Private m_LastName As String
Public Sub New(ByVal first_name As String, ByVal last_name As String)
m_FirstName = first_name
m_LastName = last_name
End Sub
Public Overrides Function ToString() As String
Return m_FirstName & " " & m_LastName
End Function
End Class
Public Class EmployeeCollection
Inherits CollectionBase
Public Sub Add(ByVal value As Employee)
List.Add(value)
End Sub
Public Function Contains(ByVal value As Employee) As Boolean
Return List.Contains(value)
End Function
Public Function IndexOf(ByVal value As Employee) As Integer
Return List.IndexOf(value)
End Function
Public Sub Insert(ByVal index As Integer, ByVal value As Employee)
List.Insert(index, value)
End Sub
Default Public ReadOnly Property Item(ByVal index As Integer) As Employee
Get
Return DirectCast(List.Item(index), Employee)
End Get
End Property
Public Sub Remove(ByVal value As Employee)
List.Remove(value)
End Sub
End Class</source>
<pre class=codeResult>A A
B B
C C
D D
E E</pre>

==Inherit CollectionBase to create your own Collection structure==

<source lang="vbnet">Option Strict On
Imports System.Collections
Public Class SortedStrings
Inherits CollectionBase
Public Function Add(ByVal value As String) As Integer
MyBase.List.Add(value)

Sort()
End Function
Default Public Property Item(ByVal index As Integer) As String
Get
Return DirectCast(MyBase.List.Item(index), String)
End Get
Set(ByVal value As String)
MyBase.List.Item(index) = value
End Set
End Property
Public Sub Sort
Dim sArr(Me.Count - 1) As String
Dim IColl As ICollection = Me
IColl.CopyTo(sArr,0)
Array.Sort(sArr)
Me.Clear
For Each s As String In sArr
Me.List.Add(s)
Next
End Sub
End Class
Public Module TestSortedStrings
Public Sub Main()
Dim sstrings As New SortedStrings()
sstrings.Add("D")
sstrings.Add("A")
sstrings.Add("C")
sstrings.Add("B")
sstrings.Add("E")

For Each sstring As String In sstrings
Console.WriteLine(sstring)
Next
End Sub
End Module</source>
<pre class=codeResult>A
B
C
D
E</pre>

← Предыдущая	Версия 16:40, 26 мая 2010
(нет различий)

VB.Net Tutorial/Collections/CollectionBase - История изменений

в 16:40, 26 мая 2010

Admin: 1 версия