microsoft-visualbasic-runtime/Extensions/IO/Path/TemporaryEnvironment.vb

#Region "Microsoft.VisualBasic::c678d44f1e3e56908d7034d70c75c991, Microsoft.VisualBasic.Core\Extensions\IO\Path\TemporaryEnvironment.vb"

' Author:
' 
'       asuka (amethyst.asuka@gcmodeller.org)
'       xie (genetics@smrucc.org)
'       xieguigang (xie.guigang@live.com)
' 
' Copyright (c) 2018 GPL3 Licensed
' 
' 
' GNU GENERAL PUBLIC LICENSE (GPL3)
' 
' 
' This program is free software: you can redistribute it and/or modify
' it under the terms of the GNU General Public License as published by
' the Free Software Foundation, either version 3 of the License, or
' (at your option) any later version.
' 
' This program is distributed in the hope that it will be useful,
' but WITHOUT ANY WARRANTY; without even the implied warranty of
' MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
' GNU General Public License for more details.
' 
' You should have received a copy of the GNU General Public License
' along with this program. If not, see <http://www.gnu.org/licenses/>.



' /********************************************************************************/

' Summaries:

'     Class TemporaryEnvironment
' 
'         Constructor: (+1 Overloads) Sub New
' 
'         Function: makeDirectoryExists
' 
'         Sub: (+2 Overloads) Dispose
' 
' 
' /********************************************************************************/

#End Region

Namespace FileIO

    ''' <summary>
    ''' Workspace model
    ''' 
    ''' 在<see cref="TemporaryEnvironment.Dispose()"/>的时候，文件夹会切换回来
    ''' </summary>
    Public Class TemporaryEnvironment : Inherits Directory
        Implements IDisposable

        ReadOnly previous$

        ''' <summary>
        ''' 如果不存在会创建目标文件夹
        ''' </summary>
        ''' <param name="newLocation"></param>
        Sub New(newLocation As String)
            Call MyBase.New(DIR:=makeDirectoryExists(newLocation))

            previous = App.CurrentDirectory
            App.CurrentDirectory = newLocation
        End Sub

        Private Shared Function makeDirectoryExists(dir As String) As String
            If Not dir.DirectoryExists Then
                Call dir.MkDIR
            End If

            Return dir
        End Function

#Region "IDisposable Support"
        Private disposedValue As Boolean ' To detect redundant calls

        ' IDisposable
        Protected Overridable Sub Dispose(disposing As Boolean)
            If Not disposedValue Then
                If disposing Then
                    ' TODO: dispose managed state (managed objects).
                    App.CurrentDirectory = previous
                End If

                ' TODO: free unmanaged resources (unmanaged objects) and override Finalize() below.
                ' TODO: set large fields to null.
            End If
            disposedValue = True
        End Sub

        ' TODO: override Finalize() only if Dispose(disposing As Boolean) above has code to free unmanaged resources.
        'Protected Overrides Sub Finalize()
        '    ' Do not change this code.  Put cleanup code in Dispose(disposing As Boolean) above.
        '    Dispose(False)
        '    MyBase.Finalize()
        'End Sub

        ' This code added by Visual Basic to correctly implement the disposable pattern.
        Public Sub Dispose() Implements IDisposable.Dispose
            ' Do not change this code.  Put cleanup code in Dispose(disposing As Boolean) above.
            Dispose(True)
            ' TODO: uncomment the following line if Finalize() is overridden above.
            ' GC.SuppressFinalize(Me)
        End Sub
#End Region
    End Class
End Namespace