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Declaring Thread in a Constructor in C#

I´m currently figuring out threads and how to work with them.
At the same time Im working on my understanding on Events/Global Events (just for context).
I defined a thread inside a object with the function the thread will use on thread.Start().
internal class Name
{
private Thread testthread;
private EventWaitHandle globalEvent;
private Eventstest evente = new Eventstest(); //Just to add some methods
public Name(Thread testthread, EventWaitHandle globalEvent)
{
this.testthread = testthread;
this.globalEvent = globalEvent;
}
public void Execute()
{
bool terminate = false;
bool eventset = false;
bool rdy = false;
while (!terminate)
{
if (evente.CheckSysEvent(globalEvent))
{
eventset = true; //This is just to check with debugger if the event was raised elsewhere
}
Thread.Sleep(100);
}
}
}
So now, like in this example in a Windows Forms App, Im trying to set an instance of this class while setting the instance of the thread at the same time (with the work method the should run later on).
Im struggling with this part here.
private void btn_runThread_Click(object sender, EventArgs e)
{
threadClass = new Name(new Thread(ProblemHere), globalEvent);
threadClass.Execute();
}
This is a button which starts the thread with the work its supposed to do.
The variable threadClass is just the initialization in the forms1.cs:
Name threadClass;
I know that it wants a delegate to pass the method which the thread should use on start.
I tried pretty much anything I found and cant make it work.
I cant just pass the method, that doesnt work.
And the stuff I found in the c# documentation is pretty much just passing the method, as far as I understood it.
Which is propably wrong.
And I just noticed, how am I able to actually call on that property/thread.start if its only created on runtime?

Not a full solution, but a bump to get you going:
What I would suggest is a little refactor like this
internal class Name
{
private Thread testthread;
private EventWaitHandle globalEvent;
private Eventstest evente = new Eventstest(); //Just to add some methods
public Name(EventWaitHandle globalEvent)
{
this.testthread = new Thread(Execute); // Creates a Thread, that is directed to execute `Execute`
this.globalEvent = globalEvent;
this.testthread.Start(); // Tells the framework to schedule the thread for execution.
}
private void Execute()
{
bool terminate = false;
bool eventset = false;
bool rdy = false;
while (!terminate)
{
if (evente.CheckSysEvent(globalEvent))
{
eventset = true; //This is just to check with debugger if the event was raised elsewhere
}
Thread.Sleep(100);
}
}
}
And in the Button handler just do
private void btn_runThread_Click(object sender, EventArgs e)
{
threadClass = new Name(globalEvent);
}
Mind that there are still a good portion of mistakes and ooopsies, but at least, this will keep your GUI thread running and you may gain an understanding to go on from here.
A totally different approach (if you are willing to consider it) would be to use a System.Windows.Forms.Timer instead. With that you can have a method called every X time, which would check the state of the globalevent as you are trying to get the thread to doing. The timer, however, makes this a little more convenient.

The typical way would be to create the thread in the constructor, as described in the answer by Fildor.
But I want to point out that using the Thread object directly is rarely the correct way to do things since there are other tools more suited for whatever you are tryibng to do:
If you want to do something compute heavy on a background thread once, and update the UI after it has been done. Use Task.Run and async/await
If you want to do something every X seconds. Use a timer. There are both timers that run on the main thread or a background thread, see differences between timers.
If you want to run an compute heavy operation in parallel, use Parallel.For, possibly in combination with Task.Run.
If you want to call IO intensive methods without freezing the UI, use async/await in combination with the appropriate Async methods.
If you want to create a producer/consumer or other processing pipeline there is the DataFlow library

Why is UI unresponsive while being programmatically controlled?

I hand-rolled a MVC-style implementation of a game that I want to autoplay. By "autoplay" I mean that the buttons that normally a user would click while playing I want a controller to automatically initiate. That way I can watch the game play itself for quality control reasons. This particular game has a lot of code, so instead of providing it as an example I've created a silly HelloWorld example using the same approach.
Before I provide the example, here is my issue: everything you see below is functional, and "works"; except for one thing: I'm unable to shut-off the autoplay because the UI becomes unresponsive and the button to turn it off won't respond to a click event.
First create a .Net 4.6.1 winforms project in a solution. (.net version probably doesn't matter as long as it is >= 4.5). Create a Form that looks like this:
In the code behind, copy paste this: (change names as needed to compile)
using System;
using System.Threading;
using System.Windows.Forms;
namespace WinformsExample
{
public partial class HelloWorldView : Form
{
private readonly HelloWorldController MyHelloWorldController;
public HelloWorldView()
{
InitializeComponent();
MyHelloWorldController = new HelloWorldController();
}
private void button1_Click(object sender, EventArgs e)
{
MyHelloWorldController.HelloWorldRequested();
if (MyHelloWorldController.IsAutomated)
{
Thread.Sleep(2000);
button1.PerformClick();
}
}
private void HelloWorldView_Load(object sender, EventArgs e)
{
MyHelloWorldController.HelloWorldRequestedEvent += OnHelloWorldRequested;
}
private void OnHelloWorldRequested(HelloWorldParameters parameters)
{
textBox1.Text += parameters.HelloWorldString + Environment.NewLine;
textBox1.Update();
}
private void button2_Click(object sender, EventArgs e)
{
MyHelloWorldController.IsAutomated = !MyHelloWorldController.IsAutomated;
if (MyHelloWorldController.IsAutomated)
{
button2.Text = "hello world - is on";
button2.Update();
button1.PerformClick();
}
else
{
button2.Text = "hello world - is off";
button2.Update();
}
}
}
}
And create a class titled HelloWorldController.cs and copy paste this in to it:
namespace WinformsExample
{
public class HelloWorldParameters
{
public string HelloWorldString { get; set; }
}
public delegate void HelloWorldEventHandler(HelloWorldParameters parameters);
public class HelloWorldController
{
private readonly HelloWorldParameters _parameters;
public event HelloWorldEventHandler HelloWorldRequestedEvent;
public bool IsAutomated { get; set; }
public HelloWorldController()
{
_parameters = new HelloWorldParameters();
}
public void HelloWorldRequested()
{
_parameters.HelloWorldString = "Hello world!!";
if (HelloWorldRequestedEvent != null)
HelloWorldRequestedEvent(_parameters);
}
}
}
...go ahead and rename things if you need to. Now build the program. Click the first button. You will see "hello world". Now click the second button, you will see "hello world" printed every 2 seconds.
The way I thought this would work is that by clicking button2 a second time, that it would stop the autoplay. However, the UI is unresponsive and the button click event never happens.
What is going on here that is causing the UI to be unresponsive and how can I fix it so that I get the intended behavior?
*UPDATE - HERE IS THE SOLUTION *
Keep everything the same as above except for HelloWorldView.cs. Remove the call to Thread.Sleep(). Drag and drop a timer from the toolbox to the design surface. You will see an icon on the bottom of the designer surface labeled
timer1
Copy paste the following code in to HelloWorldView.cs. Compile and execute. If everything is correct you should be able to turn on and off the "hello world" display by clicking the button at any time - the UI stays responsive.
using System;
using System.Windows.Forms;
namespace WinformsExample
{
public partial class HelloWorldView : Form
{
private readonly HelloWorldController MyHelloWorldController;
public HelloWorldView()
{
InitializeComponent();
MyHelloWorldController = new HelloWorldController();
}
private void onTimerTick(object sender, EventArgs e)
{
button1.PerformClick();
}
private void OnHelloWorldRequested(HelloWorldParameters parameters)
{
textBox1.Text += parameters.HelloWorldString + Environment.NewLine;
textBox1.Update();
}
private void HelloWorldView_Load(object sender, EventArgs e)
{
MyHelloWorldController.HelloWorldRequestedEvent += OnHelloWorldRequested;
}
private void button1_Click(object sender, EventArgs e)
{
MyHelloWorldController.HelloWorldRequested();
}
private void button2_Click(object sender, EventArgs e)
{
MyHelloWorldController.IsAutomated = !MyHelloWorldController.IsAutomated;
if (MyHelloWorldController.IsAutomated)
{
button2.Text = "hello world - is on";
button2.Update();
timer1.Interval = 2000;
timer1.Tick += onTimerTick;
timer1.Start();
}
else
{
timer1.Stop();
button2.Text = "hello world - is off";
button2.Update();
}
}
}
}

WinForms uses a single message pump thread (called the UI thread). (If you are unfamiliar with the concept you should research Windows messages and Windows message pump).
Thread.Sleep causes the currently executing thread the sleep, or pause, for a time. This sleep/pause is like death to the thread - it is aware of nothing and unable to do anything.
As the currently executing thread in a WinForms app is usually the UI thread - Thread.Sleep will cause the UI to become unresponsive because it is no longer able to pump messages.
An alternative design would be to use a form-based Timer. Place your game playing code in the Timer's Tick event.

What is going on here that is causing the UI to be unresponsive and how can I fix it so that I get the intended behavior?
There are essentially two reasons why your app becomes unresponsive.
1. Thread.Sleep() in UI thread
GUI applications on Windows are generally driven by messages (mouse clicks; keyboard; screen drawing) posted to it which are placed on a queue. The UI thread processes these messages one by one dispatching the message to the appropriate handler. In this way it is known as the Message Pump. If during processing one of these messages too much time elapses, then the UI will appear to freeze. Event handlers should be as fast as possible.
During your click handlers you are using Thread.Sleep(2000); which will prevent the UI thread from updating the UI of your application, in essence simulating an event handler that takes far too long to process an event. It is perhaps no different to say performing a lengthy database or WCF operation on the UI thread, hence why people tend to put such calls on a separate thread or task.
Recommend you remove the Thread.Sleep and replace it with a timer as others have indicated.
2. Infinite Recursive Loop on button1 handler
When you click button2 for the first time, the click handler for button2 is invoked where automation is enabled. You then simulate button1 being clicked via button1.PerformClick();.
During the call to button1.PerformClick, the click handler for button1 button1_Click() is invoked. It is there that you sleep for 2 seconds (which isn't healthy for the UI) but the secondary problem is that you immediately call button1.PerformClick(); from inside the button1 click handler, in essence setting up an infinite recursive loop.
If you were to remove the Thread.Sleep(2000) your app will eventually lead to a StackOverflowException. Your code as it stands now (even with the sleep) will still overflow, it's just that it will take much longer to become apparent.
Again, consider replacing it with a timer.
3. Exclusivity
It's important to note that ignoring the stack fault for a moment, the design is such that your app can't do anything else whilst this infinite loop is running. So if your game had other buttons to click; scores to display; sound effects to play; all from the point of view of the button2 handler, most likely it will never happen because it is too busy exclusively processing button1.
Conclusion
Keep UI responsive: Avoid Thread.Sleep() in your code
Avoid recursion: Don't use PerformClick() for a button whilst you are inside the click handler for said button

Your "Thread.Sleep()" call puts the UI thread to sleep. Use a Timer instead. Then terminate the Timer on the second press. (You could also do this with Tasks, if you want to use another thread you need to make the 2 threads communicate in someway so that the UI thread is the only one actually updating the UI)

Desktop applications have a so called UI thread. It's basically an infinite loop which keeps checking if something happened, such as a mouse click, and redraws the window if needed. Coding in WinAPI you would need to write this loop yourself, WinForms and other UI frameworks hide it away. But your click handler is called from inside this loop. So if your code takes too much time - like, because you call Thread.Sleep inside - the loop will not continue and will not be able to process anything that is happening to the application. This why long-running processes need to take place on a separate thread.

As others have said, you are blocking the UI thread with the Thread.Sleep and recursive button1.PerformClick(); call. You have to let the UI run as freely as possible and let it go idle quickly.
So, just for the fun of it I have rewritten your code to do just that. I've also implemented it with Microsoft's Reactive Extensions (Rx) - just NuGet "Rx-WinForms" to get the bits. Rx allows you to do some very funky things that you can't easily do with events.
Here's your form now:
public partial class HelloWorldView : Form
{
private readonly HelloWorldController MyHelloWorldController =
new HelloWorldController("Hello world!!", TimeSpan.FromSeconds(1.0));
public HelloWorldView()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
MyHelloWorldController.Messages
.ObserveOn(this)
.Subscribe(message =>
{
textBox1.Text += message + Environment.NewLine;
});
MyHelloWorldController.IsAutomateds
.ObserveOn(this)
.Subscribe(isAutomated =>
{
button2.Text = "hello world - is " + (isAutomated ? "on" : "off");
});
}
private void button1_Click(object sender, EventArgs e)
{
MyHelloWorldController.Trigger();
}
private void button2_Click(object sender, EventArgs e)
{
MyHelloWorldController.IsAutomated = !MyHelloWorldController.IsAutomated;
}
}
You'll notice that I've simplified down the UI. It really does as little as possible to update itself and to notify the HelloWorldController of its actions.
The worst part of the code are the two .Subscribe calls in Form1_Load. These are simply looking at the two observables (Rx's version of events if you like) and makes sure the events are run on the UI thread with the .ObserveOn(this) call, and then they subscribe to values produced from the HelloWorldController.
The UI is simply updating itself from the controller and telling the controller what it is doing. There is virtually no logic being performed in the UI. This is how it should be with any MVC-style coding.
Now the HelloWorldController is where the fun is.
It starts off pretty simply:
private string _message;
private TimeSpan _automatedPeriod;
public HelloWorldController(string Message, TimeSpan automatedPeriod)
{
_message = Message;
_automatedPeriod = automatedPeriod;
}
This is basically the information about what message to send to the UI and how often when the controller is automating the values.
It then tracks whether it is automated or not:
private bool _isAutomated = false;
Now it contains the Rx observables - these are like the events you were using.
private Subject<string> _messages = new Subject<string>();
public IObservable<string> Messages { get { return _messages.AsObservable(); } }
private Subject<bool> _isAutomateds = new Subject<bool>();
public IObservable<bool> IsAutomateds { get { return _isAutomateds.AsObservable(); } }
private SerialDisposable _serialSubscription = new SerialDisposable();
In Rx an IObservable<T> is something I can subscribe to to get a series of values - just like an event. The Subject<T> is something that I can manually push values into, but it also can be an IObservable<T> that can be subscribed to. It's the pair of these that lets me raise events. Think of the Subject<string> to be the equivalent of the HelloWorldRequested method in your code and the IObservable<string> to be the equivalent of the HelloWorldRequestedEvent event.
If I call _messages.OnNext("Hello") then any subscribers to IObservable<string> Messages would get a "Hello" sent to them. Just like an event.
IsAutomated looks like this:
public bool IsAutomated
{
get { return _isAutomated; }
set
{
_isAutomated = value;
_isAutomateds.OnNext(value);
if (_isAutomated)
{
this.Trigger();
}
}
}
So it does its job of updating its own internal state, but it also calls _isAutomateds.OnNext(value) to push out the updates to any subscribers of IObservable<bool> IsAutomateds. It also works out if it needs to trigger the controller to produce messages with the this.Trigger() call.
Finally the Trigger method looks like this:
public void Trigger()
{
if (_isAutomated)
{
_serialSubscription.Disposable =
Observable
.Interval(_automatedPeriod)
.StartWith(0)
.TakeUntil(_isAutomateds.Where(x => x == false))
.Subscribe(n => _messages.OnNext(_message));
}
else
{
_messages.OnNext(_message);
}
}
The easy part of this is when the _isAutomated is false then it simply sends one message out via the _messages.OnNext(_message) call.
When _isAutomated is true it uses some of the coolness of Rx to set up effectively a timer to produce values every TimeSpan _automatedPeriod. From your code you wanted every 2 seconds so the TimeSpan would be TimeSpan.FromSeconds(2.0).
Observable.Interval(_automatedPeriod) defines a timer that begins producing values after the first period of time and then every period of time between.
So the .StartWith(0) says that it should immediately produce a value when it is subscribed to.
The .TakeUntil(_isAutomateds.Where(x => x == false)) is the best part here - it says that it will take the values from the the Observable.Interval(_automatedPeriod).StartWith(0) and stop when it gets a value from _isAutomateds.Where(x => x == false) - in other words when the IsAutomated is set to false.
The .Subscribe(n => _messages.OnNext(_message)); simply pushes a value to the _messages subject so that all subscribers of IObservable<string> Messages gets their messages.
Just put all of the HelloWorldController I've given you in public class HelloWorldController { ... } and you're good to go.
The works I think like it should and shows how lightweight the UI code can be.
I hope you find this worth playing with.
You'll need to add these using's to the top of your code to get all of the code to compile:
using System.Reactive.Disposables;
using System.Reactive.Linq;
using System.Reactive.Subjects;

How to I design a class so looping is not necessary?

I have to process some records. For reasons that are unnecessary to mention, I can not loop through these records at the UI layer. The client wants to be able to simply call the middle tier using a function call, have the middle tier loop through and process the records. The problem is they want the middle tier to report back a status after each record is processed. How would I design that. For what it's worth, this is c# in .net.

A setup similar to this should work. It's untested/uncompiled so consider it pseudo-code. Also, it should ideally be asynchronous, but this will give you a starting point as an example of how to communicate changes back to the UI through eventing without the UI being aware of any "looping".
Event plumbing:
public class MyEventArgs : EventArgs
{
//add properties you want to send to the UI here.
}
public delegate void ProcessedEventHandler(object sender, MyEventArgs e);
Middle tier raises events.
public class MiddleTier
{
public event ProcessedEventHandler RecordProcessed;
//NOTE it would be best to make a tweak to do this asynchronously
//such that all records can be processed at the same time instead
//of processing them sequentially. if the method were async, you
//could do all of this without the method itself blocking.
public void Process()
{
//this loop/processing should ideally be asynchronous
foreach(var thing in whatever)
{
//process thing
//make event args
var args = new MyEventArgs(); //fill out properties
//raise event
OnProcessed(args);
}
private void OnProcessed(MyEventArgs args)
{
//follow this pattern for thread safety
var p = RecordProcessed;
if(p != null)
p(this, args);
}
}
}
Then in your UI layer:
//in some UI function
var mt = new MiddleTier();
//handle event
mt.RecordProcessed +=
(s, args) =>
{
//update UI
};
//kick things off
mt.Process();

You don't mention what technology your UI will be but assuming it is an application, you want the processing to happen on a separate thread so as to allow your UI to update.
I would look at the backgroundworker component as a starting point. It facilitates a progresschanged event you can use to notify your UI of how it getting on. Similar can be achieved using asynchronous framework.

c# Program wont respond after event fired

I'm developing a user interface for a program, and something very strange is happening.
I have a text view, 2 buttons and a progress bar. I redirectioned the output on the console to my text view. so wen I click the buttons I should receive output messages. in the beginning it was fine, but then I used some longer routines, I'm trying to log in into a web service and use web-requests.
my code works almost as It was supposed to work, I can log in and make my web requests just fine. but because the answers can become slow I created some output messages, and there my problem started.. My interface wont update until all the code I created on my event handler end's running. and when that code ends executing, I receive all the output messages all at once. I cant even move the window while the program is running..
I´m programing on c# for my first time, I had to use it because I need to use dll's.. and this kind of problem never happened before. I usually use Java.
It's like the code isn't running on the right order and it doesn´t make sense to me.. because I know my code is right because it runs on the console, and it runs while the program isn't responding..
I cant seem to understand this, should I make my events handling using threads?
class MainClass
{
public static void Main (string[] args)
{
Application.Init ();
UIMain win = new UIMain ();
win.ShowAll ();
Application.Run ();
}
}
public partial class UIMain : Gtk.Window
{
public UIMain () :
base (Gtk.WindowType.Toplevel)
{
System.Windows.Forms.Application.EnableVisualStyles ();
this.Build ();
Console.SetOut (new ControlWritter(this.textview1));
}
protected void OnButton2Clicked (object sender, EventArgs e)
{
if (entry1.Text.Equals(String.Empty) || entry2.Text.Equals(String.Empty)) {
Console.WriteLine("random output");
}
ConstantesSetup.autoSetup ();
button1.Sensitive = true;
if (!ConstantesSetup.var1) {
ConstantesSetup.routine6 ();
ConstantesSetup.routine5 ();
ConstantesSetup.routine4 ();
ConstantesSetup.routine3 ();
ConstantesSetup.routine2 ();
ConstantesSetup.var1 = true;
}
}
protected void OnButton1Clicked (object sender, EventArgs e)
{
switch (ConstantesSetup.erp) {
case "ERP":
eti_scp.autoSync (this);
break;
}
}
}
I'm sorry for the lack of code, but I don't even know were to start looking for the problem..
thanks for your time ;)

You are blocking the UI thread with long running synchronous operations. You need to run these long running operations asynchronously so that the button click event handler can return right away while your tasks run in the background.
There are several options for running tasks asynchronously but one simple option is using a BackgroundWorker. In your event handler you could do something like:
var worker = new BackgroundWorker();
worker.DoWork += (o, args) =>
{
//call long running processes here
};
worker.RunWorkerAsync();
The BackgroundWorker will also dispatch these operations onto the UI thread for you so you can update controls in the form inside the DoWork callback method.

How to respond events while a threaded operation is running in .NET

I have a class to launch background operations in a WinForms application. I need to write this background worker since my requisites are using .NET 1.1, so I cannot use BackgroundWorker, that is only available from .NET 2.0
This class get a delegate and execute it in a thread. I want the main thread to respond to events.
I also want to indicate that the operation is running setting the application cursor to Cursors.WaitCursor.
What do you think about current implementation? I'm interested in the method WaitTillThreadFinishes(), because I'm not sure about Application.DoEvents(), please read the code and share with me opinions about WaitTillThreadFinishes.
The following code executes the operation:
private object ExecuteOperation (Delegate target, params object[] parameters)
{
mTargetDelegate = target;
mTargetParameters = parameters;
mTargetThread = new Thread(new ThreadStart(ThreadProc));
mTargetThread.Name = mTargetDelegate.Method.Name;
mOperationFinished = false;
// start threaded operation
mTargetThread.Start();
// perform active waiting
WaitTillThreadFinishes();
return mTargetResult;
}
The following code is executed in a thread, simply call the delegate, and wrap exceptions:
protected virtual void ThreadProc()
{
try
{
mTargetResult = mTargetDelegate.DynamicInvoke(mTargetParameters);
}
catch (ThreadAbortException) { }
catch (Exception ex)
{
//manage exceptions here ...
}
finally
{
mOperationFinished = true;
}
}
And this is the code performs an active waiting. I'm interested on share with you. Any better option? Any pain calling Application.DoEvents() massively?
private void WaitTillThreadFinishes ()
{
// Active wait to respond to events with a WaitCursor
while (!mOperationFinished)
{
// sleep to avoid CPU usage
System.Threading.Thread.Sleep(100);
Application.DoEvents();
Cursor.Current = Cursors.WaitCursor;
}
Cursor.Current = Cursors.Default;
}
Thanks in advance.

Please let me know if i understood your question correctly.
Why dont you use an event to notify the UI that the worker finished his job?
This way, the UI doen't get blocked by the worker, and you avoid busy waiting.
Sample Implementation
public class MyBackgroundWorker
{
// Fields
private Delegate _target;
private object[] _arguments;
// Events
public event EventHandler RunWorkerStarted;
public event EventHandler<RunWorkerCompletedEventArgs> RunWorkerCompleted;
// Event Invocators
public void InvokeRunWorkerStarted()
{
var handler = RunWorkerStarted;
if (handler != null) handler(this, new EventArgs());
}
public void InvokeRunWorkerCompleted(object result)
{
var handler = RunWorkerCompleted;
if (handler != null) handler(this, new RunWorkerCompletedEventArgs(result));
}
public void RunWorkerAsync(Delegate target, params object[] arguments)
{
_target = target;
_arguments = arguments;
new Thread(DoWork).Start(arguments);
}
// Helper method to run the target delegate
private void DoWork(object obj)
{
_target.DynamicInvoke(_arguments);
// Retrieve the target delegate's result and invoke the RunWorkerCompleted event with it (for simplicity, I'm sending null)
InvokeRunWorkerCompleted(null);
}
}
internal class RunWorkerCompletedEventArgs : EventArgs
{
public RunWorkerCompletedEventArgs(object result)
{
Result = result;
}
public object Result { get; set; }
}
Usage
In the UI you can use it this way:
private void button1_Click(object sender, EventArgs e)
{
var worker = new MyBackgroundWorker();
worker.RunWorkerStarted += worker_RunWorkerStarted;
worker.RunWorkerCompleted += worker_Completed;
worker.RunWorkerAsync(new MethodInvoker(SomeLengthyOperation), null);
}
void worker_RunWorkerStarted(object sender, EventArgs e)
{
}
void worker_Completed(object sender, EventArgs e)
{
MessageBox.Show("Worker completed");
}
private void SomeLengthyOperation()
{
Thread.Sleep(5000);
}
Final Notes
Remember to Invoke() in the event handlers to access the UI thread correctly. You can also modify the worker so this is done in a safe way.

There isn't much support in 1.1 for doing this, but I'll tell you what I'd do (sorry, no code at this time).
As for the asynchronous operation, I'd use the APM to kick off and complete the asynchronous method. This is fully supported in 1.1, so no worries there.
The idea is that in the UI, you store some indication that work is being done (a boolean field, for example) and (optionally) a Timer used to "wake up" the UI on a regular basis to check on the current status of the background work and indicate this to the user.
You would set the boolean to indicate you are working in the background, call BeginInvoke() on your delegate (using the overload that takes a callback search for "Executing a Callback Method When an Asynchronous Call Completes
"), and start the Timer. When the user attempts to use the UI, you would optionally check the boolean and cancel the operation, thus preventing the user from doing something harmful while you are waiting. When the timer Ticks, you can check the status of your asynchronous method by, say, a shared field that the method writes updates to and the UI reads. For example, a double which the UI uses to update a progress bar.
Once the callback fires, you clean up your asynchronous mess (i.e., call EndInvoke, and handle any exceptions thrown, etc), turn off the Timer and reset your boolean running indication field.
By using this method, you can keep the UI completely responsive (and partially usable, depending on your overall design), can set up a mechanism to abort the background worker (through the use of another field, the reverse of the boolean mentioned earlier, and inform the user of the status of the operation.

There is occasionally a case for kicking off a thread and waiting for its return, if you are doing other things in the meantime, but in this case, with the code you have shown, it is meaningless.
If you want the threadProc to allow for events to be processed, then call doevents in that, which will free up the CPU briefly, allowing for processing.
Unless you have a particular reason for needing to thread processes, you should not do it. Getting it right - as Ian Boyd has said - is difficult, and the more you need to interact with it the harder it is. If you can run fire-and-forget threads, that is the easiest.

Ideally you start the asynchronous operation and leave your form alone (aside from maybe using the Cursors.AppStarting cursor).
When your threaded operation completes, it then needs to fire some sort of BackgroundOperationComplete event. This is where your would call from your asynchronous delegate code:
form.Invoke(BackgroundOperationComplete);
The form's BackgroundOperationComplete method is where you can handle the fact that the background operation is complete:
void BackgroundOperationComplete()
{
this.Cursor = Cursors.DefaultCursor;
lblAnswer.Text = "The thread is done";
}
If all else fails, keep the operation synchronous, and use an IProgressDialog. (brief conceptual pseudo-code from memory):
void DoStuff()
{
IProgressDialog pd = new ProgressDialog();
pd.SetTitle = "Calculating Widgets";
pd.StartTimer(PDTIMER_RESET, NULL)
pd.StartProgressDialog(this.Handle, NULL, PROGDLG_MODAL | PROGDLG_NOTIME | PROGDLG_NOPROGRESSBAR | PROGDLG_NOCANCEL, NULL);
try
{
pd.SetLine(1, "Please wait while the widgets are frobbed");
DoTheThingThatDoesTheSynchronousStuff();
}
finally
{
pd.StopProgressDialog();
}
pd = null;
}