DownloadDataCompletedEventArgs Class
Provides data for the DownloadDataCompleted event.
Assembly: System (in System.dll)
System::EventArgs
System.ComponentModel::AsyncCompletedEventArgs
System.Net::DownloadDataCompletedEventArgs
| Name | Description | |
|---|---|---|
![]() | Cancelled | Gets a value indicating whether an asynchronous operation has been canceled.(Inherited from AsyncCompletedEventArgs.) |
![]() | Error | Gets a value indicating which error occurred during an asynchronous operation.(Inherited from AsyncCompletedEventArgs.) |
![]() | Result | Gets the data that is downloaded by a DownloadDataAsync method. |
![]() | UserState | Gets the unique identifier for the asynchronous task.(Inherited from AsyncCompletedEventArgs.) |
| Name | Description | |
|---|---|---|
![]() | Equals(Object^) | Determines whether the specified object is equal to the current object.(Inherited from Object.) |
![]() | Finalize() | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.(Inherited from Object.) |
![]() | GetHashCode() | Serves as the default hash function. (Inherited from Object.) |
![]() | GetType() | |
![]() | MemberwiseClone() | |
![]() | RaiseExceptionIfNecessary() | Raises a user-supplied exception if an asynchronous operation failed.(Inherited from AsyncCompletedEventArgs.) |
![]() | ToString() | Returns a string that represents the current object.(Inherited from Object.) |
Instances of this class are passed to the DownloadDataCompletedEventHandler.
The following code example demonstrates downloading a user-specified resource.
// Sample call : DownLoadDataInBackground ("http://www.contoso.com/GameScores.html"); void DownloadDataInBackground( String^ address ) { System::Threading::AutoResetEvent^ waiter = gcnew System::Threading::AutoResetEvent( false ); WebClient^ client = gcnew WebClient; Uri ^uri = gcnew Uri(address); // Specify that the DownloadDataCallback method gets called // when the download completes. client->DownloadDataCompleted += gcnew DownloadDataCompletedEventHandler( DownloadDataCallback ); client->DownloadDataAsync( uri, waiter ); // Block the main application thread. Real applications // can perform other tasks while waiting for the download to complete. waiter->WaitOne(); }
The following method is called when the download completes.
void DownloadDataCallback( Object^ /*sender*/, DownloadDataCompletedEventArgs^ e ) { System::Threading::AutoResetEvent^ waiter = dynamic_cast<System::Threading::AutoResetEvent^>(e->UserState); try { // If the request was not canceled and did not throw // an exception, display the resource. if ( !e->Cancelled && e->Error == nullptr ) { array<Byte>^data = dynamic_cast<array<Byte>^>(e->Result); String^ textData = System::Text::Encoding::UTF8->GetString( data ); Console::WriteLine( textData ); } } finally { // Let the main application thread resume. waiter->Set(); } }
Available since 2.0
Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.


