collection.vb

大名鼎鼎的mono是.NET平台的跨平台（支持linux

'
' Collection.vb
'
' Author:
'   Chris J Breisch ([e-mail]) 
'   Mizrahi Rafael ([e-mail])
'   Boris Kirzner ([e-mail])
'

'
' Copyright (C) 2002-2006 Mainsoft Corporation.
' Copyright (C) 2004-2006 Novell, Inc (http://www.novell.com)
'
' Permission is hereby granted, free of charge, to any person obtaining
' a copy of this software and associated documentation files (the
' "Software"), to deal in the Software without restriction, including
' without limitation the rights to use, copy, modify, merge, publish,
' distribute, sublicense, and/or sell copies of the Software, and to
' permit persons to whom the Software is furnished to do so, subject to
' the following conditions:
' 
' The above copyright notice and this permission notice shall be
' included in all copies or substantial portions of the Software.
' 
' THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
' EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
' MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
' NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
' LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
' OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
' WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
'
Imports System
Imports System.Runtime.InteropServices
Imports System.Collections
Imports System.ComponentModel
Imports System.Runtime.Serialization
Imports System.Reflection

Namespace Microsoft.VisualBasic
#If NET_VER >= 2.0 Then
    '<DebuggerTypeProxy ("??")>
    <Serializable()> _
    <DebuggerDisplay("Count = {Count}")> _
    Public NotInheritable Class Collection
#Else
    Public NotInheritable Class Collection
#End If

        Implements ICollection
        Implements IList
#If NET_VER >= 2.0 Then
        Implements ISerializable
        Implements IDeserializationCallback
#End If

        ' Declarations
        Private m_Hashtable As Hashtable = New Hashtable
        Private m_HashIndexers As ArrayList = New ArrayList
        Private m_KeysCount As Integer = Integer.MinValue
        Friend Modified As Boolean = False

#If NET_VER < 2.0 Then
        Private m_Broken As Boolean
#End If

        Private Class ColEnumerator
            Implements IEnumerator

            Private currentKey As Object
            Private afterLast As Boolean = False
            Private m_col As Collection

#If NET_VER >= 2.0 Then
            Private m_Current As Object
#End If

            Public Sub New(ByRef coll As Collection)
                m_col = coll
                currentKey = Nothing
            End Sub

            Public Sub Reset() Implements System.Collections.IEnumerator.Reset
                If (m_col.Modified) Then
                    'LAMESPEC: spec says throw exception, MS doesn't
                    'throw new InvalidOperationException();
                End If
                currentKey = Nothing
                afterLast = False
            End Sub

            Public Function MoveNext() As Boolean Implements System.Collections.IEnumerator.MoveNext
                If (m_col.Modified) Then
                    'LAMESPEC: spec says throw exception, MS doesn't
                    'throw new InvalidOperationException();
                End If

                If currentKey Is Nothing And m_col.Count > 0 Then
                    currentKey = m_col.m_HashIndexers(0)
#If NET_VER >= 2.0 Then
                    m_Current = CurrentInternal
#End If
                    Return True
                End If

#If NET_VER >= 2.0 Then
                If afterLast Then
                    m_Current = Nothing
                    Return False
                End If
#End If

                Dim index As Integer = m_col.m_HashIndexers.IndexOf(currentKey)
                If index >= m_col.Count - 1 Then
                    afterLast = True
#If NET_VER >= 2.0 Then
                    m_Current = Nothing
#End If
                    Return False
                End If

                currentKey = m_col.m_HashIndexers(index + 1)
                afterLast = False

#If NET_VER >= 2.0 Then
                m_Current = CurrentInternal
#End If
                Return True
            End Function

            Public ReadOnly Property Current() As Object Implements System.Collections.IEnumerator.Current
                Get
#If NET_VER >= 2.0 Then
                    Return m_Current
#Else
                    return CurrentInternal
#End If
                End Get
            End Property

            Private ReadOnly Property CurrentInternal() As Object
                Get
                    Dim index As Integer = m_col.m_HashIndexers.IndexOf(currentKey)
                    If index > m_col.Count - 1 Then
                        Return Nothing
                    Else
                        If afterLast Then
                            If MoveNext() Then
                                Dim tmo As ColEnumerator = Me
                                Return tmo.Current()
                            Else
                                Return Nothing
                            End If
                        End If
                        Return m_col(index + 1)
                    End If
                End Get
            End Property

        End Class
        ' Constructors
        ' Properties
        Private ReadOnly Property IsReadOnly() As Boolean Implements System.Collections.IList.IsReadOnly
            Get
                Return False
            End Get
        End Property
        Private ReadOnly Property IsSynchronized() As Boolean Implements System.Collections.ICollection.IsSynchronized
            Get
                Return m_Hashtable.IsSynchronized
            End Get
        End Property

        Private ReadOnly Property SyncRoot() As Object Implements System.Collections.ICollection.SyncRoot
            Get
                Return m_Hashtable.SyncRoot
            End Get
        End Property

        Private ReadOnly Property IsFixedSize() As Boolean Implements System.Collections.IList.IsFixedSize
            Get
                Return False
            End Get
        End Property

        Public ReadOnly Property Count() As Integer
            Get
                Return IList_Count
            End Get
        End Property

        Private ReadOnly Property IList_Count() As Integer Implements System.Collections.IList.Count
            Get
                Return m_HashIndexers.Count
            End Get
        End Property

#If NET_VER >= 2.0 Then
        <EditorBrowsable(EditorBrowsableState.Advanced)> _
        Default Public Overloads ReadOnly Property Item(ByVal index As Object) As Object
#Else
        Default Public Overloads ReadOnly Property Item(ByVal index As Object) As Object
#End If
            Get
                If index Is Nothing Then Throw New IndexOutOfRangeException("Argument 'Index' is not a valid index.")

                If TypeOf index Is Integer Then
                    Return Item(CInt(index))
                Else
                    Dim idx As Integer = m_HashIndexers.IndexOf(index)
                    If idx = -1 Then
                        Throw New ArgumentException("Argument 'Index' is not a valid value.")
                    End If
                    Return Item(idx + 1)
                End If
            End Get
        End Property

        Default Public Overloads ReadOnly Property Item(ByVal index As Integer) As Object
            Get
                'The behaviour of Collection.Item is NOT the same as the IList.Item interface implementation.
                index = index - 1

                If index > Count - 1 Or index < 0 Then
                    Throw New IndexOutOfRangeException("Collection1 index must be in the range 1 to the size of the collection.")
                End If

                Return m_Hashtable(m_HashIndexers(index))
            End Get
        End Property

#If NET_2_0 Then
        Default Public Overloads ReadOnly Property Item(ByVal index As String) As Object
            Get
                Return Item(CObj(index))
            End Get
        End Property
#End If

        Private Property IList_Item(ByVal index As Integer) As Object Implements System.Collections.IList.Item
            Get
#If NET_VER < 2.0 Then
                If m_Broken Then Throw New InvalidCastException ()
#End If
                If index < 0 AndAlso Count > 0 Then
                    'Oh man this behaviour is weird...
                    index = 0
                End If

                If index > Count - 1 Or index < 0 Then
                    Throw New ArgumentOutOfRangeException("Collection1 index must be in the range 1 to the size of the collection.")
                End If

                Return m_Hashtable(m_HashIndexers(index))

            End Get
            Set(ByVal Value As Object)
#If NET_VER < 2.0 Then
                m_Broken = True
#End If
                If index < 0 AndAlso Count > 0 Then
                    'Oh man this behaviour is weird...
                    index = 0
                End If