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OpenWriteCompletedEventHandler Delegate

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

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

'Declaration
Public Delegate Sub OpenWriteCompletedEventHandler ( _
	sender As Object, _
	e As OpenWriteCompletedEventArgs _
)

Parameters

sender
Type: System.Object

The source of the event.

e
Type: System.Net.OpenWriteCompletedEventArgs

A OpenWriteCompletedEventArgs containing event data.

When you create a OpenWriteCompletedEventHandler 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.

The following code example demonstrates opening a stream to write data to be uploaded.

		Public Shared Sub OpenResourceForPosting(ByVal address As String)

			Dim client As WebClient = New WebClient()
			'  Specify that the OpenWriteCallback method gets called 
			'  when the writeable stream is available. 
			AddHandler client.OpenWriteCompleted, AddressOf OpenWriteCallback2
                        Dim uri as Uri = New Uri(address)
			client.OpenWriteAsync(uri)
			'  Applications can perform other tasks 
			'  while waiting for the upload to complete. 
		End Sub

The following method is called when the stream is available.

        Private Shared Sub OpenWriteCallback2(ByVal sender As Object, ByVal e As OpenWriteCompletedEventArgs)

            Dim body As Stream = Nothing 
            Dim s As StreamWriter = Nothing 

            Try

                body = CType(e.Result, Stream)
                s = New StreamWriter(body)
                s.AutoFlush = True
                s.Write("This is content data to be sent to the server.")
            Finally 

                If Not s Is Nothing Then

                    s.Close()
                End If 

                If Not body Is Nothing Then

                    body.Close()
                End If 
            End Try 
        End Sub

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

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