OpenWriteCompletedEventArgs クラスとは何？わかりやすく解説 Weblio辞書

.NET Framework クラスライブラリリファレンス

索引トップ用語の索引ランキング

OpenWriteCompletedEventArgs クラス

メモ : このクラスは、.NET Framework version 2.0 で新しく追加されたものです。

OpenWriteCompleted イベントのデータを提供します。

名前空間: System.Net
アセンブリ: System (system.dll 内)
構文

Visual Basic (宣言)

Public Class OpenWriteCompletedEventArgs
    Inherits AsyncCompletedEventArgs

Visual Basic (使用法)

Dim instance As OpenWriteCompletedEventArgs

public class OpenWriteCompletedEventArgs :
 AsyncCompletedEventArgs

C++

public ref class OpenWriteCompletedEventArgs
 : public AsyncCompletedEventArgs

public class OpenWriteCompletedEventArgs extends
 AsyncCompletedEventArgs

JScript

public class OpenWriteCompletedEventArgs extends
 AsyncCompletedEventArgs

解説

このクラスのインスタンスは OpenWriteCompletedEventHandler メソッドに渡されます。

使用例

ストリームを開いてアップロード対象のデータを書き込むコード例を次に示します。

Visual Basic

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

public static void OpenResourceForPosting
 (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);
    // Applications can perform other tasks
    // while waiting for the upload to complete.
}

ストリームが利用可能な場合、次のメソッドが呼び出されます。

Visual Basic

Public 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

public 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 ();
        }
    }
}