WebClient.OpenWriteCompleted イベント

定義

リソースにデータを書き込むストリームを開く非同期操作が完了したときに発生します。

public:
 event System::Net::OpenWriteCompletedEventHandler ^ OpenWriteCompleted;
public event System.Net.OpenWriteCompletedEventHandler? OpenWriteCompleted;
public event System.Net.OpenWriteCompletedEventHandler OpenWriteCompleted;
member this.OpenWriteCompleted : System.Net.OpenWriteCompletedEventHandler 
Public Custom Event OpenWriteCompleted As OpenWriteCompletedEventHandler 
Public Event OpenWriteCompleted As OpenWriteCompletedEventHandler 

イベントの種類

次のコード例は、このイベントのイベント ハンドラーを設定する方法を示しています。

void OpenResourceForWriting2( String^ address )
{
   WebClient^ client = gcnew WebClient;
   Uri ^uri = gcnew Uri(address);

   // Specify that the OpenWriteCallback method gets called
   // when the writeable stream is available.
   client->OpenWriteCompleted += gcnew OpenWriteCompletedEventHandler( OpenWriteCallback2 );
   client->OpenWriteAsync( uri, "POST" );

   // Applications can perform other tasks
   // while waiting for the upload to complete.
}
public static void OpenResourceForWriting2(string address)
{
    WebClient client = new WebClient();
    Uri uri = new Uri(address);

    // Specify that the OpenWriteCallback method gets called
    // when the writeable stream is available.
    client.OpenWriteCompleted += new OpenWriteCompletedEventHandler(OpenWriteCallback2);
    client.OpenWriteAsync(uri, "POST");
    // Applications can perform other tasks
    // while waiting for the upload to complete.
}
Public Shared Sub OpenResourceForWriting2(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, "POST")
    '  Applications can perform other tasks
    '  while waiting for the upload to complete.
End Sub

次のコード例は、このイベントのハンドラーの実装を示しています。

void OpenWriteCallback2( Object^ /*sender*/, OpenWriteCompletedEventArgs^ e )
{
   Stream^ body = nullptr;
   StreamWriter^ s = nullptr;
   try
   {
      body = dynamic_cast<Stream^>(e->Result);
      s = gcnew StreamWriter( body );
      s->AutoFlush = true;
      s->Write( "This is content data to be sent to the server." );
   }
   finally
   {
      if ( s != nullptr )
      {
         s->Close();
      }
      if ( body != nullptr )
      {
         body->Close();
      }
   }

}
private static void OpenWriteCallback2(Object sender, OpenWriteCompletedEventArgs e)
{
    Stream body = null;
    StreamWriter s = null;

    try
    {
        body = (Stream)e.Result;
        s = new StreamWriter(body);
        s.AutoFlush = true;
        s.Write("This is content data to be sent to the server.");
    }
    finally
    {
        if (s != null)
        {
            s.Close();
        }

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

注釈

注意

WebRequestHttpWebRequestServicePointWebClient は廃止されており、新しい開発には使用しないでください。 代わりに HttpClient を使用してください。

このイベントは、リソースにデータを送信するために使用されるストリームを開く非同期操作が完了するたびに発生します。 これらの操作は、OpenWriteAsync メソッドを呼び出すことによって開始されます。

OpenWriteCompletedEventHandler は、このイベントのデリゲートです。 OpenWriteCompletedEventArgs クラスは、イベント データをイベント ハンドラーに提供します。

イベントの処理方法の詳細については、「イベントの処理と発生」を参照してください。

適用対象