DownloadStringCompletedEventArgs.Result 属性

定义

命名空间:

System.Net

程序集:

System.Net.WebClient.dll

Source:

WebClient.cs

获取由 DownloadStringAsync 方法下载的数据。

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

public string Result { get; }

member this.Result : string

Public ReadOnly Property Result As String

属性值

String

String，包含已下载的数据。

示例

下面的代码示例显示此属性的值。

void DownloadStringCallback2( Object^ /*sender*/, DownloadStringCompletedEventArgs^ e )
{

   // If the request was not canceled and did not throw
   // an exception, display the resource.
   if (  !e->Cancelled && e->Error == nullptr )
   {
      String^ textString = dynamic_cast<String^>(e->Result);
      Console::WriteLine( textString );
   }
}

private static void DownloadStringCallback2(Object sender, DownloadStringCompletedEventArgs e)
{
    // If the request was not canceled and did not throw
    // an exception, display the resource.
    if (!e.Cancelled && e.Error == null)
    {
        string textString = (string)e.Result;

        Console.WriteLine(textString);
    }
}

Private Shared Sub DownloadStringCallback2(ByVal sender As Object, ByVal e As DownloadStringCompletedEventArgs)

    '  If the request was not canceled and did not throw
    '  an exception, display the resource.
    If e.Cancelled = False AndAlso e.Error Is Nothing Then

        Dim textString As String = CStr(e.Result)
        Console.WriteLine(textString)
    End If
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。