OpenReadCompletedEventArgs.Result 屬性

定義

命名空間:

System.Net

組件:

System.Net.WebClient.dll

來源:

WebClient.cs

取得包含由 DownloadDataAsync 方法下載之資料的可讀取資料流。

public:
 property System::IO::Stream ^ Result { System::IO::Stream ^ get(); };

public System.IO.Stream Result { get; }

member this.Result : System.IO.Stream

Public ReadOnly Property Result As Stream

屬性值

Stream

Stream，包含下載的資料。

範例

下列程式代碼範例會使用這個屬性傳回的數據流。

void OpenReadCallback2( Object^ /*sender*/, OpenReadCompletedEventArgs^ e )
{
   Stream^ reply = nullptr;
   StreamReader^ s = nullptr;
   try
   {
      reply = dynamic_cast<Stream^>(e->Result);
      s = gcnew StreamReader( reply );
      Console::WriteLine( s->ReadToEnd() );
   }
   finally
   {
      if ( s != nullptr )
      {
         s->Close();
      }
      if ( reply != nullptr )
      {
         reply->Close();
      }
   }

}

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

備註

您應該先檢查 和 Cancelled 屬性，Error再使用這個屬性所傳回的數據。 Error如果屬性的值是Exception物件，或Cancelled屬性的值是 true，異步操作未正確完成，而且Result屬性值無效。