static void GetResponseCallback(IAsyncResult ar)
{
// Fetch our state information
RequestResponseState state = (RequestResponseState)ar.AsyncState;
// Fetch the response which has been generated
state.response = state.request.EndGetResponse(ar);
// Store the response stream in the state
state.stream = state.response.GetResponseStream();
// Stash an Encoding for the text. I happen to know that
// my web server returns text in ISO-8859-1 - which is
// handy, as we don't need to worry about getting half
// a character in one read and the other half in another.
// (Use a Decoder if you want to cope with that.)
//state.encoding = Encoding.GetEncoding(28591);
state.encoding = Encoding.UTF8;
// Now start reading from it asynchronously
state.stream.BeginRead(state.buffer, 0, state.buffer.Length, new AsyncCallback(ReadCallback), state);
}
static void RUN()
{
WebRequest request = WebRequest.Create(PageUrl);
RequestResponseState state = new RequestResponseState();
state.request = request;
// Lock the object we'll use for waiting now, to make
// sure we don't (by some fluke) do everything in the other threads
// before getting to Monitor.Wait in this one. If we did, the pulse
// would effectively get lost!
lock (finishedLock)
{
request.BeginGetResponse(new AsyncCallback(GetResponseCallback), state);
Console.WriteLine("Waiting for response...");
// Wait until everything's finished. Normally you'd want to
// carry on doing stuff here, of course.
Monitor.Wait(finishedLock);
}
}
static void ReadCallback(IAsyncResult ar)
{
// Fetch our state information
RequestResponseState state = (RequestResponseState)ar.AsyncState;
// Find out how much we've read
int len = state.stream.EndRead(ar);
// Have we finished now?
if (len == 0)
{
// Dispose of things we can get rid of
((IDisposable)state.response).Dispose();
((IDisposable)state.stream).Dispose();
ReportFinished(state.text.ToString());
return;
}
// Nope - so decode the text and then call BeginRead again
state.text.Append(state.encoding.GetString(state.buffer, 0, len));
state.stream.BeginRead(state.buffer, 0, state.buffer.Length, new AsyncCallback(ReadCallback), state);
}
