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App not processing events while trying to open database connection

I am writing a Windows Forms app in C# with Visual Studio 2022 on a Windows 10 machine. The app connects to an Azure database, which works fine. My issue is that sometimes it takes several seconds to connect (maybe 10 or so), or if there is an error it goes all the way to the timeout limit (usually 20 to 30 seconds) before coming back with whatever error message there is.
I am trying to provide some visual feedback to the user during this time, but the application does not appear to be processing any events, so whatever type of feedback I'm trying to send does not get done until the operation completes (at which point it is moot).
Any ideas on how to deal with this? Do I need to open the database on a different thread, and if so, will that be an issue throughout the rest of the app whenever I use the database object opened on a different thread?
I'm trying something simple, like gradually adding a row of dots, like so:
private void InitCloudDatabase()
{
Boolean success = true;
WorkingTimer.Enabled = true;
WorkingTimer.Start();
try
{
AzureAgDatabase db = new AzureAgDatabase();
db.OpenConnection();
}
catch
{
success = false;
}
WorkingTimer.Stop();
pbCloudResult.Image = (success) ? Properties.Resources.icons8_done_96 :
Properties.Resources.Red_X___Fail;
}
private void WorkingTimer_Tick(object sender, EventArgs e)
{
lblCloud.Text += " .";
if (lblCloud.Text.Contains(" . . . . . . . . . . ."))
{
lblCloud.Text = "Database Connection (Cloud)";
}
}

I haven't really worked with Windows Forms before, but in most UI based applications, you should reserve the UI Thread for just UI operations and move all time consuming tasks (Compute or I/O) to a different thread to ensure that the UI is still responsive.
In the case of Windows Forms, looks like you have a BackgroundWorker class that you can use to offload the DB operations into. Here is a walkthrough in the official docs that you can refer to.
Another approach would be to use the Task class to run your database code asynchronously, with lesser code compared to the first approach. You would simply wrap statements that take time in a Task.Run call and have follow up statements in a continuation task.

How to force phantomjs to finish navigating

I have a problem that my phantomjs loads one site too slow, always at least 60 seconds though on other sites like google.com it takes less than 1 second.
PhantomJSDriverService service = PhantomJSDriverService.CreateDefaultService();
service.IgnoreSslErrors = true;
service.LoadImages = false;
service.ProxyType = "none";
service.HideCommandPromptWindow = true;
using (IWebDriver driver = new PhantomJSDriver(service ))
{
driver.Navigate().GoToUrl("http://abc.xyz"); //blocks too long
...
}
Is there any way to force it finish loading after reaching some point so the script will continue?

I see what you are asking now. You have a long loading page that you want to stop after the relevant stuff loads. I run into this same issue with some of the sites that we have at work but I have not tried a programmatic solution. Sorry, I don't know phantomjs but I found some links that I think would be helpful.
The way I would approach it is to wait for the DOMContentLoaded event to fire and then send an ESC to the page. At least that's what I do manually to stop the long loading files that I don't care about so that the execution can continue.
I found this question How can I wait for the page to be ready in PhantomJS? Here's the relevant part:
var page = require('webpage').create();
var system = require('system');
page.onInitialized = function() {
page.onCallback = function(data) {
console.log('Main page is loaded and ready');
//Do whatever here
};
page.evaluate(function() {
document.addEventListener('DOMContentLoaded', function() {
window.callPhantom();
}, false);
console.log("Added listener to wait for page ready");
});
};
page.open('https://www.google.com', function(status) {});
Once you detect DOMContentLoaded, use sendkeys() to send the ESC key. I honestly don't know if this will work but it's where I would start. Hopefully it will get you started.

I've just found out the reasons why the phantomjs load so slow because the target web has too many extensions, ads... so I switch to chrome and use adblock like Running Selenium WebDriver using Python with extensions (.crx files)

Selenium and Internet Explorer Driver

I'm trying to run some tests with C# and InternetExplorerDriver.
This code is executed on Windows Server 2012, 64 bit.
Right after navigation to a new URL, I'm calling a function that waits until a page loads\20 seconds timeout.
private bool waitForPageToLoad()
{
try
{
int timeout = int.Parse(ConfigurationManager.AppSettings["TimeoutForCustomExpression"]);
IWait<IWebDriver> wait = new OpenQA.Selenium.Support.UI.WebDriverWait(m_driver, TimeSpan.FromSeconds(timeout));
wait.Until(driver1 => ((IJavaScriptExecutor)m_driver).ExecuteScript("return document.readyState").Equals("complete"));
}
catch//(Exception e) //timeout
{
log(e.Message + e.StackTrace);
return false;
}
return true;
}
The function works great for every browser other than IE.
On IE, I the following error in my log:
JavaScript error (UnexpectedJavaScriptError) at
OpenQA.Selenium.Support.UI.DefaultWait1.PropagateExceptionIfNotIgnored(Exception
e) in
c:\Projects\WebDriver\trunk\dotnet\src\WebDriver.Support\UI\DefaultWait.cs:line
222 at OpenQA.Selenium.Support.UI.DefaultWait1.Until[TResult](Func`2
condition) in
c:\Projects\WebDriver\trunk\dotnet\src\WebDriver.Support\UI\DefaultWait.cs:line
180 at MainClass.waitForPageToLoad()
I have no idea why it happens.
Could somebody help me out here?
Sincerely,
Adam.

Without seeing all that extra information that Arran requested, it's hard to help you understand the error.
However if you're just looking for a quick fix that works in all browsers, I always just use
Thread.sleep(int milliseconds);
for my Selenium tests in C# that need to wait for a page to load or a certain element to render before continuing.

BackgroundWorker in MVC3 application freezes UI

I'm developing MVC3 based web application, which at one point needs to cache large amount of data from some external database. Process takes about 10-30 min (depending on a traffic) so I put it in BackgroundWorker. When you click particular button on the webpage, using ajax it just access other method in controller, depending on the returned value proper information is displayed on user interface.
Controller:
if (IsDbLocked())
{
return this.Json(new
{
success = false,
message = "There is already an update requested by other user on the way."
});
}
this.model.DataUpdateBegin();
return this.Json(new { success = true });
Model:
public void DataUpdateBegin()
{
var backgroundWorker = new BackgroundWorker
{
WorkerSupportsCancellation = false,
WorkerReportsProgress = true
};
backgroundWorker.DoWork += this.DataUpdateWorkerDoWork;
backgroundWorker.ProgressChanged += this.DataUpdaterWorkerProgressChanged;
backgroundWorker.RunWorkerCompleted += this.DataUpdaterWorkerRunWorkerCompleted;
if (this.DataUpdateLockDb(true))
{
backgroundWorker.RunWorkerAsync();
}
}
Now when I do update, UI still freezes. While debuging controller I can see, that it starts BackgroundWorker and instantly continues to return statement (with success = true), but then it just finishes, and nothing else happens (returned message never reaches webpage).
I can see page from other browser/user and everything works ok, but this particular thread is locked for several minutes (not entire 10-30 min, as it's get unlocked after about 5 min - timeout?)
My question is, what I did wrong and how to fix it. I expect backgroundWorker to just run in the background, and free user to move around page wherever he wish. Also making an entry in database and making some external application just fetch it and do all the work (in real background) is not an option for me.

Do not use Background worker like this. Yes, the work will be done within another thread, but still in scope of that web request. Web requests are not ment to be alive for 30 minutes, there are plenty of things that can go wrong (timeouts, app pool restart, other IIS behaviour..)
If you have this type of long-running task, you should do it in some worker - windows service, maybe console application, etc. and from web you just start it (console) or set it to be done (message queue, azure queue)
Also, i hope you are not locking database (you method IsDbLocked()) for 30 minutes? Just do your import in transaction and use proper isolation level (read commited) so DB work normally all the time and the changes are there instantly when import finishes.

I'm developing MVC3 based web application
... so I put it in BackgroundWorker
BackgroundWorker is designed to work with Windows (forms) application; to achieve similar in web application, use Task.Factory.StartNew or Thread (more primitive)

WatiN seems to not find JavaScript alert

I have a web application that, under some conditions, pop up JavaScript alert()s that I need to react to in a WatiN test. Google pointed me at Handling alerts in WATIN from way back in 2007 that seemed promising, and I adapted the example code in that post into the following (anonymized):
private void MyAssert(IE browser, WatinHelper helper)
{
AlertDialogHandler alertDialogHandler = new AlertDialogHandler();
using (new UseDialogOnce(browser.DialogWatcher, alertDialogHandler))
{
// DoWrong() causes a JavaScript alert(); false means use nowait.
DoWrong(helper, false);
alertDialogHandler.WaitUntilExists(10 /*seconds*/);
if (!alertDialogHandler.Exists())
{
Assert.Fail("No JavaScript alert when it should have been there");
}
alertDialogHandler.OKButton.Click();
}
SecondAssert(browser);
}
However, while the alert is displayed virtually instantaneously (as it is supposed to) when DoWrong() is called, the call to alertDialogHandler.WaitUntilExists() eventually fails with a WatiNException: Dialog not available within 10 seconds... The only problem was that I could see that the dialog most definitely was up on the screen.
I'm probably missing something simple; can someone point me in the right direction please?
I have also tried the following two variants, and some variations of them, with no luck; I keep getting the same error.
AlertDialogHandler alertDialogHandler = new AlertDialogHandler();
DoWrong(helper, false);
System.Diagnostics.Stopwatch stopwatch = new System.Diagnostics.Stopwatch();
stopwatch.Start();
do
{
}
while (!alertDialogHandler.Exists() && stopwatch.Elapsed.TotalMilliseconds < 3000);
Assert.IsTrue(alertDialogHandler.Exists(), "No JavaScript alert when it should have been there");
alertDialogHandler.OKButton.Click();
SecondAssert(browser);
and
AlertDialogHandler alertDialogHandler = new AlertDialogHandler();
browser.DialogWatcher.Add(alertDialogHandler);
DoWrong(helper, false);
alertDialogHandler.WaitUntilExists();
alertDialogHandler.OKButton.Click();
browser.WaitForComplete();
Assert.IsFalse(alertDialogHandler.Exists());
SecondAssert(browser);
Yes, I know that code is getting a bit ugly, but right now I'm mostly trying to get it to work at all. If it sits for a few seconds cooking the CPU at 100% utilization because of the tight loop in my second attempt, but only does what I need it to (plain and simple, dismiss that alert()), it's OK.

This is an issue with WatiN and IE8 and the way IE8 changed the way it creates popups. The issue is fixed in the current code available at the Sourceforge SVN repository for the project. Get it, compile it and your problem is solved.
A new release of WatiN will be available before the end of this year.
HTH,
Jeroen