Downloading files in an array

[Broggy69]

Downloading files in an array.


I created an array of files I need to download. However when I run the code I get System.NotSupportedException: WebClient does not support concurrent I/O operations.

However I added:

AddHandler _WClient.DownloadProgressChanged, AddressOf WClient_ProgressChanged
AddHandler _WClient.DownloadFileCompleted, AddressOf WC_DownloadComplete

And running in a for loop.

If I add a message box I can wait for file to download and then click OK, but I do not believe I should have to do that.

Here is the code I have:


Imports System.Net
Imports System.ComponentModel

Public Class Form1

Dim WithEvents WClient As New WebClient

Public Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

Dim ftpsite As String = "ftp://mysite.com/"

'*** For Third Party Files ***
Dim DB_3rd_FTPFiles() As String = {"File1.zip",
"File2.exe",
File3.zip",
File4.zip"}



For Each ThirdFTP As String In DB_3rd_FTPFiles

If ThirdFTP = "File2.zip" Then
WClient.Credentials = New NetworkCredential("user", "Password")
Dim Downloadpath2 As New Uri(ftpsite & "Folder2/" & ThirdFTP)
AddHandler _WClient.DownloadProgressChanged, AddressOf WClient_ProgressChanged
AddHandler _WClient.DownloadFileCompleted, AddressOf WC_DownloadComplete

Try
WClient.DownloadFileAsync(Downloadpath2, "C:\FakeEDrive\Install\3rdParty\" & ThirdFTP)
Catch ex As Exception
MsgBox(ex.ToString)
End Try

'WClient.Dispose() 'I tried this no change
'MsgBox("Wait for " & ThirdFTP & " to be downloaded") 'When using this message box and wait until I see file downloads then it works.
End If

WClient.Credentials = New NetworkCredential("user", "password")
Dim Downloadpath As New Uri(ftpsite & ThirdFTP)
AddHandler WClient.DownloadProgressChanged, AddressOf WClient_ProgressChanged
AddHandler WClient.DownloadFileCompleted, AddressOf WC_DownloadComplete

Try
WClient.DownloadFileAsync(Downloadpath, "C:\FakeEDrive\Install\3rdParty\" & ThirdFTP)
Catch ex As Exception
MsgBox(ex.ToString)
End Try

' WClient.Dispose()
'MsgBox("Wait for " & ThirdFTP & " to be downloaded")
Next

End Sub


Public Sub WC_DownloadComplete(sender As Object, e As AsyncCompletedEventArgs)

Using webClient As New Net.WebClient
RemoveHandler webClient.DownloadFileCompleted, AddressOf WC_DownloadComplete
End Using

End Sub

Private Sub WClient_ProgressChanged(ByVal sender As Object, ByVal e As DownloadProgressChangedEventArgs) Handles WClient.DownloadProgressChanged

ProgressBar1.Value = e.ProgressPercentage
'Progress bar only updates after file has been downloaded

End Sub

End Class



Any help is appreciated

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