global.asax

Other things about csharp. you could learn from this

<%@ Import namespace="System.Threading" %>
<%@ Import namespace="System.Text" %>

<Script language="C#" runat=server>
  MyAsyncResult asyncResult;

  public override void Init(){
    BeginEventHandler beginEvent = new BeginEventHandler(Begin);
    EndEventHandler endEvent = new EndEventHandler(End);

    AddOnBeginRequestAsync(beginEvent, endEvent);
  }

  // Begin Event Handler
  public IAsyncResult Begin(Object source, EventArgs e, AsyncCallback callback, Object extraData) {
    asyncResult = new MyAsyncResult(this.Context, callback, extraData);

    return asyncResult;
  }

  // End Event Handler  
  public void End (IAsyncResult ar){
  }


  // Async implementation class
  internal class MyAsyncResult : IAsyncResult {
    AsyncCallback callback;
    object asyncState;
    Thread thread;
    HttpContext context;
    bool isCompleted = false;

    internal MyAsyncResult(HttpContext context, AsyncCallback callback, object asyncState){
      this.callback = callback;
      this.asyncState = asyncState;
      this.context = context;
   
      thread = new Thread(new ThreadStart(CallStockQuoteWebService));
      thread.Start();
    }

    public object AsyncState {
      get {
        return asyncState;
      } 
    }

    public WaitHandle AsyncWaitHandle { 
      get { 
        return null; 
      } 
    }

    public bool CompletedSynchronously { 
      get { 
        return false; 
      } 
    }

    public bool IsCompleted {
      get { 
        return isCompleted; 
      } 
    }

    public void QuoteCallBack(IAsyncResult ar) {
      QuoteService quote = new QuoteService();
      QuoteDetails[] d = quote.EndGetQuotes(ar);

      context.Application["QuoteDetails"] = d;

      isCompleted = true;
      callback(this);
    }

    public void CallStockQuoteWebService() {
      QuoteService quote = new QuoteService();

      quote.BeginGetQuotes(new AsyncCallback(QuoteCallBack), null);
    }
  }

</Script>