WCF server client async callback with object - wcf

Question

I have Server and Client.
The client call a method on the server, The server in response have to prepare a Dictionary and send back to client.
This operation might take time.
It should be async. I read instructions and examples.
Mostly the BeginXXX and EndXXX IAsyncResult. But If i need the server to return Dictionary of objects. How do i implement this ?
I thought when sending a callback delegate I can send a signature of one of the clients' functions as delegate and when Server finish it will invoke the delegate with the proper dictionary data.

Answer 1

1) Adding service reference in VS (or SLSvcUtil) generates handy proxy code with events for Silverlight projects. You can use it to implement callback's pattern for your 'service/server agent' if you want. You can use this code with regular .net apps as well with some modifications.
2) VS for .Net project can generate proxy with async methods. SvcUtil - too.
3) For real long running operations you can use WCF services with callbacks (+ some binding restrictions).

Answer 2

If I understand you in a right way, you're asking about this (based on eLibrary project):
WCF Server side:
EBooksLibraryEntities ebe = new EBooksLibraryEntities();
public List<Book> tabBooks()
{
return ebe.Books.ToList();
}
Client side:
ServiceReference1.Service1Client sr = new ServiceReference1.Service1Client();
List<ServiceReference1.Book> llb = new List<ServiceReference1.Book>();
private void GetBooksByAuthor()
{
sr.tabBooksByAuthorCompleted += new EventHandler<ServiceReference1.tabBooksByAuthorCompletedEventArgs>(sr_tabBooksByAuthorCompleted);
sr.tabBooksByAuthorAsync();
}
void sr_tabBooksByAuthorCompleted(object sender, ServiceReference1.tabBooksByAuthorCompletedEventArgs e)
{
foreach (var item in e.Result)
{
yourList.Add(item);
}
}