OpenReadCompletedEventArgs Classe

Definição

public ref class OpenReadCompletedEventArgs : System::ComponentModel::AsyncCompletedEventArgs

public class OpenReadCompletedEventArgs : System.ComponentModel.AsyncCompletedEventArgs

type OpenReadCompletedEventArgs = class
    inherit AsyncCompletedEventArgs

Public Class OpenReadCompletedEventArgs
Inherits AsyncCompletedEventArgs

Herança

Object

EventArgs

AsyncCompletedEventArgs

OpenReadCompletedEventArgs

Exemplos

O exemplo de código a seguir demonstra o download de um recurso para leitura.

public static void OpenResourceForReading2(string address)
{
    WebClient client = new WebClient();
    Uri uri = new Uri(address);

    client.OpenReadCompleted += new OpenReadCompletedEventHandler(OpenReadCallback2);
    client.OpenReadAsync(uri);
}

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

O método a seguir é chamado quando o download é concluído.

private static void OpenReadCallback2(Object sender, OpenReadCompletedEventArgs e)
{
    Stream reply = null;
    StreamReader s = null;

    try
    {
        reply = (Stream)e.Result;
        s = new StreamReader(reply);
        Console.WriteLine(s.ReadToEnd());
    }
    finally
    {
        if (s != null)
        {
            s.Close();
        }

        if (reply != null)
        {
            reply.Close();
        }
    }
}

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

Comentários

Instâncias dessa classe são passadas para OpenReadCompletedEventHandler métodos.