OpenReadCompletedEventArgs.Result 属性

定义

命名空间:

System.Net

程序集:

System.Net.WebClient.dll

Source:

WebClient.cs

获取可读流，该可读流包含由 DownloadDataAsync 方法下载的数据。

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

属性值

Stream

Stream，包含已下载的数据。

示例

下面的代码示例使用此属性返回的流。

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

注解

在使用此属性返回的数据之前，应检查 Error 和 Cancelled 属性。 Error如果属性的值为 Exception 对象或Cancelled属性的值为 true，则异步操作未正确完成，Result并且该属性的值将无效。