Async requests to a web service

Question

How to make async requests to a webservice from a Thread?

Answer 1

Here is a solution using WCF.

Service Code FileService.svc

public class FileService
{
    [OperationContract]
    public byte[] GetFile(string filename)
    {
        byte[] File;
        //do logic

        return File;
    }
}

Client Code

public int requested_file_count = 5;
public list filenames;

public FileServiceClient svc 

//Constructor
public Example()
{
   svc = new FileServiceClient();
} 

Public void GetFiles()
{
    //Initialise the list of names and set the count of files received     
    filenames = new list(5);
    requested_file_count = filenames.Count; 

   svc.GetFileCompleted += new EventHandler(GetFile_Completed);

   //Call the Async Method passing it the file name and setting the userstate to 1;

   svc.GetFileAsync(filenames[0],1);
}

void GetFile_Completed(object Sender, GetFileCompletedEventArgs e)
{
   if (e.UserState == requested_file_count)
   {
     //All files have been downloaded
   }
   else
   {
      svc.GetFileAsync(filenames[e.UserState],++e.UserState);
   }

   //Do Something with the downloaded file
   byte[] filedata = e.result;
}