User guide
Callback with Client
This example assumes that the following callback function has been defined.
public static void CallbackWithClient(IAsyncResult asyncResult)
{
try {
AmazonS3Client s3Client = (AmazonS3Client) asyncResult.AsyncState;
PutObjectResponse response = s3Client.EndPutObject(asyncResult);
Console.WriteLine("Finished PutObject operation with client callback");
}
catch (AmazonS3Exception s3Exception) {
//
// Code to process exception
//
}
}
The following line of code calls BeginPutObject and specifies the preceding callback function.When
the PutObject operation completes, the callback function is called. In this example, the call to
BeginPutObject specifies the Amazon S3 client object for the state parameter.The callback function
uses the client to call the EndPutObject method to retrieve the server response. Because any exceptions
that occurred during the operation will be received when the callback calls EndPutObject, this call is
placed within a try block.
asyncResult = client.BeginPutObject(request, CallbackWithClient, client);
Callback with State Object
This example assumes that the following class and callback function have been defined.
class ClientState
{
AmazonS3Client client;
DateTime startTime;
public AmazonS3Client Client
{
get { return client; }
set { client = value; }
}
public DateTime Start
{
get { return startTime; }
set { startTime = value; }
}
}
public static void CallbackWithState(IAsyncResult asyncResult)
{
try {
ClientState state = asyncResult.AsyncState as ClientState;
AmazonS3Client s3Client = (AmazonS3Client)state.Client;
Version v2.0.0
29
AWS SDK for .NET Developer Guide
Asynchronous API for .NET 3.5