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DownloadStringCompletedEventHandler Delegate
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DownloadStringCompletedEventHandler Delegate

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

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

'Declaration
Public Delegate Sub DownloadStringCompletedEventHandler ( _
	sender As Object, _
	e As DownloadStringCompletedEventArgs _
)

Parameters

sender
Type: System.Object

The source of the event.

e
Type: System.Net.DownloadStringCompletedEventArgs

A DownloadStringCompletedEventArgs that contains event data.

When you create a DownloadStringCompletedEventHandler 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 downloading a string asynchronously.

		'  Sample call : DownloadStringInBackground2 ("http:' www.contoso.com/GameScores.html") 
		Public Shared Sub DownloadStringInBackground2(ByVal address As String)

			Dim client As WebClient = New WebClient()

			'  Specify that the DownloadStringCallback2 method gets called 
			'  when the download completes. 
			AddHandler client.DownloadStringCompleted, AddressOf DownloadStringCallback2
                        Dim uri as Uri = New Uri(address)
			client.DownloadStringAsync(uri)
		End Sub

The following method is called when the download completes.

        Private Shared Sub DownloadStringCallback2(ByVal sender As Object, ByVal e As DownloadStringCompletedEventArgs)

            '  If the request was not canceled and did not throw 
            '  an exception, display the resource. 
            If e.Cancelled = False AndAlso e.Error Is Nothing Then 

                Dim textString As String = CStr(e.Result)
                Console.WriteLine(textString)
            End If 
        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

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8
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