Multithreading accepts value and return value - asp.net

Question

Hi guys, I wrote the following code to return a pdf report. The code is based on a multi-threading sample code. Can you guys provide some feedback about it, I am new to mulit-thread.
Much appriciate !
Jeffery
public delegate void StreamResultDelegate(Stream streamResults);
public class GenerateReport
{
private StreamResultDelegate callback;
public GenerateReport(StreamResultDelegate _callback)
{
callback = _callback;
}
public void ThreadProc()
{
if (callback != null)
{
callback(Testing());
}
}
public Stream Testing()
{
var reportsService = new ReportsService();
var nameValueCollection = new NameValueCollection();
byte[] pdfReportContents = reportsService.GetReport("/Rocket.Reports/RocketReport", nameValueCollection);
var stream = new MemoryStream(pdfReportContents);
return stream;
}
}
//following
[HandleError]
public class HomeController : Controller
{
private Stream streamTesting = null;
public void StreamResultCallBack(Stream s)
{
streamTesting = s;
}
public FileStreamResult GeneratePdfReport()
{
var g = new GenerateReport(_callback: new StreamResultDelegate(StreamResultCallBack));
var t = new Thread(new ThreadStart(g.ThreadProc));
t.Start();
t.Join();
HttpContext.Response.AddHeader("content-disposition", "attachment; filename=Rockets_List_Printout.pdf");
return new FileStreamResult(streamTesting, "application/pdf");
}}

Answer 1

I would suggest to use async controllers -> MSDN and stop using threads in controller methods=)

Answer 2

My suggestion is make a private object to store the result. It's the easiest way
update
public delegate void work_handler(Stream streamResults);
public class Report
{
public object Result = null;
private Thread workThread = new ...;
public void Work(object param)
{
this.Result = ....;
// signal finish. eg. if winapp use someControl.Invoke(signal_Handler);
// for web app use this.Session["isDone"] = true;
}
// for .net 4.0
private object param = null;
public void Work()
{
// for serial invoking
var taskOption = System.Threading.Tasks.TaskCreationOptions.LongRunning;
System.Threading.Tasks.Task task = new System.Threading.Tasks.Task(() => {... }, taskOption);
// for multiple method parallel invoke
System.Threading.Tasks.Parallel.Invoke(() => { this.Result = genReport(param); }, () => {... }, () => {...});
}
}