OpenReadCompletedEventHandler Delegate

 

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

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

Public Delegate Sub OpenReadCompletedEventHandler (
	sender As Object,
	e As OpenReadCompletedEventArgs
)

Parameters

sender
Type: System.Object

The source of the event.

e
Type: System.Net.OpenReadCompletedEventArgs

A OpenReadCompletedEventArgs containing event data.

When you create a OpenReadCompletedEventHandler 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 downloading a resource for reading.

Public Shared Sub OpenResourceForReading2(ByVal address As String)

	Dim client As WebClient = New WebClient()
	AddHandler client.OpenReadCompleted, AddressOf OpenReadCallback2
                      Dim uri as Uri = New Uri(address)
	client.OpenReadAsync(uri)                        
End Sub

The following method is called when the download completes.

Private Shared Sub OpenReadCallback2(ByVal sender As Object, ByVal e As OpenReadCompletedEventArgs)

    Dim reply As Stream = Nothing
    Dim s As StreamReader = Nothing

    Try

        reply = CType(e.Result, Stream)
        s = New StreamReader(reply)
        Console.WriteLine(s.ReadToEnd())
    Finally

        If Not s Is Nothing Then

            s.Close()
        End If

        If Not reply Is Nothing Then

            reply.Close()
        End If
    End Try
End Sub

.NET Framework
Available since 2.0
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
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