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DownloadDataCompletedEventArgs Class

Definition

Provides data for the DownloadDataCompleted event.

C#
public class DownloadDataCompletedEventArgs : System.ComponentModel.AsyncCompletedEventArgs
Inheritance
DownloadDataCompletedEventArgs

Examples

The following code example demonstrates downloading a user-specified resource.

C#
// Sample call : DownLoadDataInBackground ("http://www.contoso.com/GameScores.html");
public static void DownloadDataInBackground(string address)
{
    System.Threading.AutoResetEvent waiter = new System.Threading.AutoResetEvent(false);
    WebClient client = new WebClient();
    Uri uri = new Uri(address);

    // Specify that the DownloadDataCallback method gets called
    // when the download completes.
    client.DownloadDataCompleted += new 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.

C#
private static void DownloadDataCallback(Object sender, DownloadDataCompletedEventArgs e)
{
    System.Threading.AutoResetEvent waiter = (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 == null)
        {
            byte[] data = (byte[])e.Result;
            string textData = System.Text.Encoding.UTF8.GetString(data);

            Console.WriteLine(textData);
        }
    }
    finally
    {
        // Let the main application thread resume.
        waiter.Set();
    }
}

Remarks

Instances of this class are passed to the DownloadDataCompletedEventHandler.

Properties

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)

Methods

Equals(Object)

Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode()

Serves as the default hash function.

(Inherited from Object)
GetType()

Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone()

Creates a shallow copy of the current Object.

(Inherited from Object)
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)

Applies to

Product Versions
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1