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UploadFileCompletedEventHandler Delegate
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UploadFileCompletedEventHandler Delegate

Represents the method that will handle the UploadFileCompleted event of a WebClient.

Namespace:  System.Net
Assembly:  System (in System.dll)

Public Delegate Sub UploadFileCompletedEventHandler ( _
	sender As Object, _
	e As UploadFileCompletedEventArgs _
Dim instance As New UploadFileCompletedEventHandler(AddressOf HandlerMethod)


Type: System.Object

The source of the event.

Type: System.Net.UploadFileCompletedEventArgs

A UploadFileCompletedEventArgs that contains event data.

When you create a UploadFileCompletedEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate. For more information about event handler delegates, see Events and Delegates.

The following code example demonstrates asynchronously uploading a file.

		'  Sample call: UploadFileInBackground("http:' www.contoso.com/fileUpload.aspx", "data.txt") 
		Public Shared Sub UploadFileInBackground(ByVal address As String, ByVal fileName As String)

			Dim waiter As System.Threading.AutoResetEvent = New System.Threading.AutoResetEvent(False)
			Dim client As WebClient = New WebClient()
			Dim method As String = "POST" 
                         Dim uri as Uri =  New Uri(address)

			'  Specify that that UploadFileCallback method gets called 
			'  when the file upload completes. 
			AddHandler client.UploadFileCompleted, AddressOf UploadFileCallback
			client.UploadFileAsync(uri, method, fileName, waiter)

			'  Block the main application thread. Real applications 
			'  can perform other tasks while waiting for the upload to complete.
			Console.WriteLine("File upload is complete.")
		End Sub
// Sample call: UploadFileInBackground("http://www.contoso.com/fileUpload.aspx", "data.txt")
void UploadFileInBackground (String* address, String* fileName)
    System::Threading::AutoResetEvent* waiter = new System::Threading::AutoResetEvent (false);
    WebClient* client = new WebClient ();
    String* method = S"POST";

    // Specify that that UploadFileCallback method gets called
    // when the file upload completes.
    client->UploadFileCompleted += new UploadFileCompletedEventHandler (UploadFileCallback);
    client->UploadFileAsync (address, method, fileName, waiter);

    // Block the main application thread. Real applications
    // can perform other tasks while waiting for the upload to complete.
    waiter->WaitOne ();
    Console::WriteLine (S"File upload is complete.");

The following method is called when the upload completes.

Private Shared Sub UploadFileCallback(ByVal sender As Object, ByVal e As System.Net.UploadFileCompletedEventArgs)

    Dim waiter As System.Threading.AutoResetEvent = CType(e.UserState, System.Threading.AutoResetEvent)

        Dim reply As String = System.Text.Encoding.UTF8.GetString(e.Result)
        '  If this thread throws an exception, make sure that 
        '  you let the main application thread resume.
    End Try 
End Sub
void UploadFileCallback (Object* /*sender*/, UploadFileCompletedEventArgs* e)
    System::Threading::AutoResetEvent* waiter = dynamic_cast<System::Threading::AutoResetEvent*>(e->UserToken);;
        String* reply = System::Text::Encoding::UTF8->GetString (e->Result);

        Console::WriteLine (reply);
        // If this thread throws an exception, make sure that
        // you let the main application thread resume.
        waiter->Set ();

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0

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