[سؤال] ايقاف مؤقت للتحميل واستناف من حيث توقف

PHP كود :

Private thrDownload As Thread
        Private strResponse As Stream
        Private strLocal As Stream
        Private webRequest As HttpWebRequest
        Private webResponse As HttpWebResponse
        Private Shared PercentProgress As Integer
        Private Delegate Sub UpdateProgessCallback(BytesRead As Int64, TotalBytes As Int64)
        Private goPause As Boolean = False 

PHP كود :

Private Sub btnDownload_Click(sender As Object, e As EventArgs)
            If thrDownload IsNot Nothing AndAlso thrDownload.ThreadState = ThreadState.Running Then
MessageBox.Show _ 
("A download is already running", _
 "Download in progress", MessageBoxButtons.OK, MessageBoxIcon.[Error])
            Else
                lblProgress.Text = "Download Starting"
                thrDownload = New Thread(New ParameterizedThreadStart(AddressOf Download))
                thrDownload.Start(0)
                btnPauseResume.Enabled = True
                btnPauseResume.Text = "Pause"
            End If
        End Sub 

PHP كود :

Private Sub UpdateProgress(BytesRead As Int64, TotalBytes As Int64)
            PercentProgress = Convert.ToInt32((BytesRead * 100) / TotalBytes)
            prgDownload.Value = PercentProgress
            lblProgress.Text = "Downloaded " + BytesRead + " out of " + TotalBytes + " (" + PercentProgress + "%)"
        End Sub
        Private Sub Download(startPoint As Object)
            Try
                Dim startPointInt As Integer = Convert.ToInt32(startPoint)
                webRequest = DirectCast(WebRequest.Create(txtUrl.Text), HttpWebRequest)
                webRequest.AddRange(startPointInt)
                webRequest.Credentials = CredentialCache.DefaultCredentials
                webResponse = DirectCast(webRequest.GetResponse(), HttpWebResponse)
                Dim fileSize As Int64 = webResponse.ContentLength
                strResponse = webResponse.GetResponseStream()
                If startPointInt = 0 Then
                    strLocal = New FileStream(txtPath.Text, FileMode.Create, FileAccess.Write, FileShare.None)
                Else
                    strLocal = New FileStream(txtPath.Text, FileMode.Append, FileAccess.Write, FileShare.None)
                End If
                Dim bytesSize As Integer = 0
                Dim downBuffer As Byte() = New Byte(2047) {}
                While (InlineAssignHelper(bytesSize, strResponse.Read(downBuffer, 0, downBuffer.Length))) > 0
                    strLocal.Write(downBuffer, 0, bytesSize)
                    Me.Invoke(New UpdateProgessCallback(AddressOf Me.UpdateProgress), _ 
                                        New Object() {strLocal.Length, fileSize + startPointInt})
                    If goPause = True Then
                        Exit While
                    End If
                End While
            Finally
                strResponse.Close()
                strLocal.Close()
            End Try
        End Sub
        Private Shared Function InlineAssignHelper(Of T)(ByRef target As T, value As T) As T
            target = value
            Return value
        End Function
                Public Sub New()
            InitializeComponent()
        End Sub 

PHP كود :

        Private Sub btnStop_Click(sender As Object, e As EventArgs)
            thrDownload.Abort()
            webResponse.Close()
            strResponse.Close()
            strLocal.Close()
            prgDownload.Value = 0
            lblProgress.Text = "Download Stopped"
            btnPauseResume.Enabled = False
        End Sub 

PHP كود :

Private Sub btnPauseResume_Click(sender As Object, e As EventArgs)
            If thrDownload IsNot Nothing Then
                If btnPauseResume.Text = "Pause" Then
                    goPause = True
                    btnPauseResume.Text = "Resume"
                    webResponse.Close()
                    strResponse.Close()
                    strLocal.Close()
                    thrDownload.Abort()
                Else
                    goPause = False
                    btnPauseResume.Text = "Pause"
                    Dim startPoint As Long = 0
                    If File.Exists(txtPath.Text) Then
                        startPoint = New FileInfo(txtPath.Text).Length
                    Else
                        MessageBox.Show("The file you choosed to resume doesn't exist.", _ 
                                                "Could not resume", MessageBoxButtons.OK, MessageBoxIcon.[Error])
                    End If
                    lblProgress.Text = "Download Resuming"
                    thrDownload = New Thread(New ParameterizedThreadStart(AddressOf Download))
                    thrDownload.Start(startPoint)
                    btnPauseResume.Enabled = True
                End If
            Else
                MessageBox.Show("A download does not appear to be in progress.", _ 
                                "Could not pause", MessageBoxButtons.OK, MessageBoxIcon.[Error])
            End If
        End Sub 

كود :

Module Module1

    Private Declare Function InternetGetConnectedState Lib "wininet" (ByRef dwflags As Long, ByVal dwReserved As Long) As Long

    Private Const CONNECT_LAN As Long = &H2

    Private Const CONNECT_MODEM As Long = &H1

    Private Const CONNECT_PROXY As Long = &H4

    Private Const CONNECT_OFFLINE As Long = &H20

    Private Const CONNECT_CONFIGURED As Long = &H40

    Private Const CONNECT_RAS As Long = &H10





    Public Function IsWebConnected(Optional ByRef ConnType As String = "") As Boolean

        Dim dwflags As Long

        Dim WebTest As Boolean

        WebTest = InternetGetConnectedState(dwflags, 0&)

        Select Case WebTest

            Case dwflags And CONNECT_LAN : ConnType = "LAN"

            Case dwflags And CONNECT_MODEM : ConnType = "Modem"

            Case dwflags And CONNECT_PROXY : ConnType = "Proxy"

            Case dwflags And CONNECT_OFFLINE : ConnType = "Offline"

            Case dwflags And CONNECT_CONFIGURED : ConnType = "Configured"

            Case dwflags And CONNECT_RAS : ConnType = "Remote"

        End Select

        IsWebConnected = WebTest



    End Function

End Module

كود :

If IsWebConnected() Then

            'أذا كان الانتترنت يعمل يمكنت ودع كود لاستكمال التحميل بعد توقف الانترنت

        Else

            'اذا توقف الانترنت عن العمل يمكنك وضع كود التوقف اذاتوقف الانترنت

        End If

        'يفضل وضع الكود فى timer