DownloadDataAysnc doesn't show progress

[steve_rm]

Hello,

VS 2008 SP1

I am using the DownloadDataAysnc. But the ProgressChanged event doesn't show progress until after the data has been downloaded.

Even when I try and download a data which is contained in a big file. The programs remains responsive so I know it is doing something. However, it is when the progress has completed that the progressChanged event fires.

I known this as the progressChanged and the DownloadDataCompleted fire immediately after each other. However, they should be a pause as the file is quite big.

This is the code snippet I am currently using. And the output below. What is strange the e.progresspercentage is 100%. And seems to get called twice.

Many thanks for any advise,

Results:
Progress changed Version userstate: [ Version1 ]
progressBar1.Value [ 100 ]
Progress changed Version userstate: [ Version1 ]
progressBar1.Value [ 100 ]
Completed data: [ 1.0.11 ]

Private Sub UpdateAvailable()
    Dim wbCheckUpdates As New WebClient()
    AddHandler wbCheckUpdates.DownloadProgressChanged, AddressOf wbCheckUpdates_DownloadProgressChanged
    AddHandler wbCheckUpdates.DownloadDataCompleted, AddressOf wbCheckUpdates_DownloadDataCompleted
    Dim df As New DownloadFiles()
    Dim webServerURL As String = df.webServerPath
    
    wbCheckUpdates.DownloadDataAsync(New Uri(Path.Combine(webServerURL, "version.txt")), "Version1")
End Sub

Private Sub wbCheckUpdates_DownloadProgressChanged(ByVal sender As Object, ByVal e As DownloadProgressChangedEventArgs)
    Console.WriteLine("Progress version changed userstate: [ " & e.UserState & " ]")
    progressBar1.Value = e.ProgressPercentage
    Console.WriteLine("progressBar1.Value [ " & Me.progressBar1.Value & " ]")
End Sub

Private Sub wbCheckUpdates_DownloadDataCompleted(ByVal sender As Object, ByVal e As DownloadDataCompletedEventArgs)
    Dim result As Byte() = e.Result
    Console.WriteLine("Completed data: [ " & System.Text.ASCIIEncoding.[Default].GetString(result) & " ]")
End Sub

[mendhak]

Tried your code, works fine. The only thing I can think of is that the txt file you're downloading isn't big enough nor was the 'big' file that you tried. I decided to try it with a large file, so I used one which I found recently on the Pwnie Awards website.

Try this:

Private Sub UpdateAvailable()
        Dim wbCheckUpdates As New WebClient()
        AddHandler wbCheckUpdates.DownloadProgressChanged, AddressOf wbCheckUpdates_DownloadProgressChanged
        AddHandler wbCheckUpdates.DownloadDataCompleted, AddressOf wbCheckUpdates_DownloadDataCompleted
        'Dim df As New DownloadFiles()
        'Dim webServerURL As String = df.webServerPath
 
        wbCheckUpdates.DownloadDataAsync(New Uri("http://www.sophsec.com/nice_report.mp3"), "Version1")
    End Sub

The song is awful though, don't listen to it. Also make sure that the progressbar's maximum value has been set to 100.