WCF - Upload a file to a service with a progress bar in the client

Question

Hi all,

 

I'm currently experimenting WCF, i'm pretty new to this whole thing actually. I'm using VB.NET (VS2005). So here's the thing: I'm building a small test application using WCF to upload a file to a service. I created 2 ways of uploading my file, both work perfectly. I can send the file in chunks or stream it. I tried to add a progress bar so I could see the progress on the client side. Works perfect with the chunk upload, but I can't seem to get it to work with streaming. I tried using a callback, but it seems that I won't receive any callback before the whole process is done. I do know that's normal since I didnt use "IsOneWay:=True"but I do not want to use this attribute because I don't want the process to continue before the file is totally uploaded.

 

Is there any way to send some feedback from my service to my client to monitor progress?

 

Here are parts of my code:

 

Service

 

<ServiceContract(CallbackContract:=GetType(IServiceUploadFichierCallBack), SessionMode:=SessionMode.Required)> _

Public Interface IServiceUploadFichier

<OperationContract()> Sub UploaderFichierStream(ByVal pfStream As Stream)

End Interface

 

Public Interface IServiceUploadFichierCallBack

<OperationContract(IsOneWay:=True)> Sub MAJFloodStream(ByVal pintStream As Integer)

End Interface

 

 

Upload function

 

Public Sub UploaderFichierStream(ByVal pfStream As System.IO.Stream) Implements IServiceUploadFichier.UploaderFichierStream

Dim outstream As FileStream = File.Open(mstrDestination, FileMode.Create, FileAccess.Write)

Dim content() As Byte

ReDim content(0)

Const bufferLen As Integer = 4096

Dim buffer(bufferLen) As Byte

Dim count As Integer = 0

 

Callback = OperationContext.Current.GetCallbackChannel(Of IServiceUploadFichierCallBack)()

count = pfStream.Read(buffer, 0, bufferLen)

 

While (count > 0)

Try

     Console.Write(".")

     outstream.Write(buffer, 0, count)

     Callback.MAJFloodStream(count)

     count = pfStream.Read(buffer, 0, bufferLen)

Catch ex As Exception

     Call MsgBox(ex.Message)

End Try

End While

outstream.Close()

pfStream.Close()

End Sub

 

 

 

This is what I use on the client side:

 

Public Class CallbackHandler

Implements ServiceUploadFichier.IServiceUploadFichierCallback

Public Sub MAJFloodStream(ByVal pintStream As Integer) Implements ServiceUploadFichier.IServiceUploadFichierCallback.MAJFloodStream

Form1.ProgressBar2.Value = Form1.ProgressBar2.Value + pintStream

End Sub

End Class

 

Private Sub cmdShareStream_Click_1(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdShareStream.Click

 

Dim Callback As InstanceContext = New InstanceContext(New CallbackHandler)

Dim service As New ServiceUploadFichier.ServiceUploadFichierClient(Callback)

Dim infoFichier As New ServiceUploadFichier.MessageInfoFichier

Dim fstream As FileStream = New FileStream(txtSource.Text, FileMode.Open)

Dim dblAvant As Double

Dim dblApres As Double

 

service.Open()

 

Try

dblAvant = Timer

infoFichier.Destination = txtDestination.Text

service.InitialiserFichier("", "", infoFichier.Destination)

ProgressBar2.Value = 0

ProgressBar2.Maximum = fstream.Length

service.UploaderFichierStream(fstream)

dblApres = Timer

lblTempsStream.Text = (dblApres - dblAvant).ToString("0.00")

Call MsgBox("Source: " & txtDestination.Text & vbCrLf & "Destination: " & txtAdresseSharepoint.Text)

Catch ex As Exception

Call MsgBox(ex.Message)

End Try

 

fstream.Close()

service.Close()

End Sub

 

 

I think I posted the most important parts, don't hesitate to ask I more is needed to find the problem

 

Thanks in advance,

 

Fred

Answer 1

Please ref to the following post:

 

http://forums.microsoft.com/MSDN/ShowPost.aspx?PostID=1837514&SiteID=1

 

Answer 2

Here is another post: http://seanmcilvenna.com/blog/11-solutions/20-detecting-upload-progress-with-wcf