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async method doesn't execute all the way through

I have a method that adds some data to my database, it worked fine a while ago but now it has just stopped working.
I found out with debugging that my async method gets called but then just stops in the middle and the Answers are never getting added:
private async Task CreateNewQuestion()
{
if (newQuestion.QuestionType is null)
{
noType = true;
return;
}
else if (Answers.Count == 0)
{
noAnswer = true;
return;
}
else if (newQuestion.QuestionType is not null)
{
List<Question> questioncount = new List<Question>();
questioncount = await questionRepo.GetQuestionByQuizId(QuizId);
_order = questioncount.Count + 1;
newQuestion.QuestionOrderId = _order;
newQuestion.AnswerType = _answerType;
newQuestion.QuestionUrl = _questionUrlConverted;
await questionRepo.AddQuestionWithAnswers(newQuestion, Answers); <-- THIS IS WHERE THE METHOD GETS CALLED
noType = false;
questions = await questionRepo.GetQuestionByQuizId(QuizId);
var quiz = quizRepo.GetQuizById(QuizId);
Navigation.NavigateTo($"/Quiz/AddQuestionWithId/{QuizId}", true);
}
}
and here is the method:
public async Task AddQuestionWithAnswers(Question newQuestion, List<Answer> answers)
{
if(newQuestion is not null && answers.Count > 0)
{
_context.Questions.Add(newQuestion);
await _context.SaveChangesAsync(); <-- THIS IS WHERE IT JUST STOPS TO EXECUTE
var answerQuestionItem = await GetQuestionById(newQuestion.QuestionId);
if(answerQuestionItem is not null)
{
foreach(var answer in answers)
{
answer.Question = answerQuestionItem;
_context.Answers.Add(answer);
await _context.SaveChangesAsync();
}
}
}
}
It also doesn't even go back to the method that called the method, just to my razor component and nothing happens.
Any ideas how I can fix this?

UI only partly responsive while running tasks and updating ui

i have the following ui -
For each line connection to crm should be tested. This is done in separate thread.
The test status of the connection to crm system is then updated in last column.
The problem is that the ui is only partly reponsive during threads run and updating of the ui, i.e.
i would like to click through the lines whilst updating.
Here is my code:
private async void btnTestAllConnections_Click(object sender, EventArgs e)
{
await TestConnectionsAsync();
}
private async Task TestConnectionsAsync()
{
try
{
int idxConn = columnLookup[ColumnIndex.Connection].Index;
if (lvInitParameters.Items.Count == 0)
return;
ManagedConnection connection = null;
btnTestAllConnections.Visible = false;
btnTestConnection.Visible = false;
panel2.Enabled = false;
panel3.Enabled = false;
tableLayoutPanel1.Enabled = false;
btnCancelTest.Visible = true;
List<Task> tasks = new List<Task>();
var cts = new CancellationTokenSource();
CancellationToken token = cts.Token;
foreach (ListViewItem lvi in lvInitParameters.Items)
{
InitParamProxy currentProfile = (InitParamProxy)lvi.Tag;
lvi.SubItems[idxConn].Text = "Testing...";
Task<bool> result =null;
try
{
result = Task.Run(
() =>
{
try
{
connection = currentProfile.ManagedConnection;
return connection?.ConnectionSuccess ?? false;
}
catch (Exception ex)
{
// crm exception
return false;
}
}, token);
if (token.IsCancellationRequested)
{
Console.WriteLine("\nCancellation requested in continuation...\n");
token.ThrowIfCancellationRequested();
}
ListViewItem testItem =
items.Where(si => ((InitParamProxy)lvi.Tag).ProfileKey.Equals(((InitParamProxy)si.Tag).ProfileKey)).SingleOrDefault();
lvi.SubItems[idxConn].Text = (result.Result) ? "Success" : "Fail";
if (testItem != null)
testItem.SubItems[idxConn].Text = (result.Result) ? "Success" : "Fail";
}
catch
{
ListViewItem testItem =
items.Where(si => ((InitParamProxy)lvi.Tag).ProfileKey.Equals(((InitParamProxy)si.Tag).ProfileKey)).SingleOrDefault();
lvi.SubItems[idxConn].Text = "Canceled";
if (testItem != null)
testItem.SubItems[idxConn].Text = "Canceled";
}
tasks.Add(result);
}
Task.WaitAll(tasks.ToArray());
btnTestAllConnections.Visible = true;
btnTestConnection.Visible = true;
panel2.Enabled = true;
panel3.Enabled = true;
tableLayoutPanel1.Enabled = true;
btnCancelTest.Visible = false;
}
catch (Exception)
{
}
}

In the end of your method you have
Task.WaitAll(tasks.ToArray());
This will block until all tasks are done. You should instead use WhenAll
await Task.WhenAll(tasks.ToArray());
You are also using result.Result in several places, and this also blocks. This should be replaced by awaiting the task, i.e. await result

Alternatives for Monitor (Wait, PluseAll) in Async Tasks in C#

I implemented Task synchronization using Monitor in C#.
However, I have read Monitor should not be used in asynchronous operation.
In the below code, how do I implement Monitor methods Wait and PulseAll with a construct that works with Task (asynchronous operations).
I have read that SemaphoreSlim.WaitAsync and Release methods can help.
But how do they fit in the below sample where multiple tasks need to wait on a lock object, and releasing the lock wakes up all waiting tasks ?
private bool m_condition = false;
private readonly Object m_lock = new Object();
private async Task<bool> SyncInteralWithPoolingAsync(
SyncDatabase db,
List<EntryUpdateInfo> updateList)
{
List<Task> activeTasks = new List<Task>();
int addedTasks = 0;
int removedTasks = 0;
foreach (EntryUpdateInfo entryUpdateInfo in updateList)
{
Monitor.Enter(m_lock);
//If 5 tasks are waiting in ProcessEntryAsync method
if(m_count >= 5)
{
//Do some batch processing to obtian values to set for adapterEntry.AdapterEntryId in ProcessEntryAsync
//.......
//.......
m_condition = true;
Monitor.PulseAll(m_lock); // Wakes all waiters AFTER lock is released
}
Monitor.Exit(m_lock);
removedTasks += activeTasks.RemoveAll(t => t.IsCompleted);
Task processingTask = Task.Run(
async () =>
{
await this.ProcessEntryAsync(
entryUpdateInfo,
db)
.ContinueWith(this.ProcessEntryCompleteAsync)
.ConfigureAwait(false);
});
activeTasks.Add(processingTask);
addedTasks++;
}
}
private async Task<bool> ProcessEntryAsync(SyncDatabase db, EntryUpdateInfo entryUpdateInfo)
{
SyncEntryAdapterData adapterEntry =
updateInfo.Entry.AdapterEntries.FirstOrDefault(e => e.AdapterId == this.Config.Id);
if (adapterEntry == null)
{
adapterEntry = new SyncEntryAdapterData()
{
SyncEntry = updateInfo.Entry,
AdapterId = this.Config.Id
};
updateInfo.Entry.AdapterEntries.Add(adapterEntry);
}
m_condition = false;
Monitor.Enter(m_lock);
while (!m_condition)
{
m_count++;
Monitor.Wait(m_lock);
}
m_count--;
adapterEntry.AdapterEntryId = .... //Set Value obtained form batch processing
Monitor.Exit(m_lock);
}
private void ProcessEntryCompleteAsync(Task<bool> task, object context)
{
EntryProcessingContext ctx = (EntryProcessingContext)context;
try
{
string message;
if (task.IsCanceled)
{
Logger.Warning("Processing was cancelled");
message = "The change was cancelled during processing";
}
else if (task.Exception != null)
{
Exception ex = task.Exception;
Logger.Warning("Processing failed with {0}: {1}", ex.GetType().FullName, ex.Message);
message = "An error occurred while synchronzing the changed.";
}
else
{
message = "The change was successfully synchronized";
if (task.Result)
{
//Processing
//...
//...
}
}
}
catch (Exception e)
{
Logger.Info(
"Caught an exception while completing entry processing. " + e);
}
finally
{
}
}
Thanks

Set a WPF Mahapps Progress Dialog

I'm trying to replace my ProgressBar to a Progress Dialog using Mahapps.
So I started writing this:
private void btnClick(object sender, RoutedEventArgs e)
{
ConfRelais();
}
public async void ConfRelais()
{
var controller = await this.ShowProgressAsync("hey", "hoy");
controller.Maximum = 128;
while (flag == 0)
{
string data = RelayBoard_Port.ReadTo("\r\n");
if (data == "ok") { controller.SetMessage("Done Process");
flag = 1; }
else { controller.SetProgress(Int32.Parse(data)); }
}
await controller.CloseAsync();
}
But the progress dialog only displays when it's over.. As I'm still a beginner in c# maybe I'm missing some importants points to setup that kind of function.

You should execute the loop on a background thread:
public async void ConfRelais()
{
var controller = await this.ShowProgressAsync("hey", "hoy");
controller.Maximum = 128;
await Task.Run(() =>
{
while (flag == 0)
{
string data = RelayBoard_Port.ReadTo("\r\n");
if (data == "ok")
{
controller.SetMessage("Done Process");
flag = 1;
}
else { controller.SetProgress(Int32.Parse(data)); }
}
});
await controller.CloseAsync();
}
A single thread cannot both update the UI and execute your loop simultaneously.
You also don't really need a flag. You could just break out of the loop when you receive "ok":
while (true)
{
string data = RelayBoard_Port.ReadTo("\r\n");
if (data == "ok")
{
controller.SetMessage("Done Process");
break;
}
else { controller.SetProgress(Int32.Parse(data)); }
}

How the async Task return conditionally

Hi am trying to return for an async method task conditionally. Below is the way I tried.
public string DoMessage(MyObj obj)
{
string returnStatus = "Processing...";
var storageAccount = CloudStorageAccount.DevelopmentStorageAccount;
var queueClient = storageAccount.CreateCloudQueueClient();
var queue = queueClient.GetQueueReference(ConfigurationManager.AppSettings["QueueName"]);
if (queue.CreateIfNotExists()) {
}
var msg = CloudQueueMessageExtensions.Serialize(obj);
queue.AddMessage(msg);
//Task processTask = RunMessageProces();
var t = Task.Run(() => RunMessageProces());
t.Wait();
return returnStatus;
}
private async Task<string> RunMessageProces()
{
statusProcess = "Your message successfully inserted in process queue.";
await Task.Run(() => {
lock (_oQueue)
{
if (flagProcessing == true) //return when queue processing alredy started
{
return statusProcess; //Error ..??? how to return
}
flagProcessing = true; //else start processing the queue till there are messages.
}
});
statusProcess = ProcessMyMessage();
return statusProcess;
}
private string ProcessMyMessage() {...}
What I am missing? How to return string in between conditionally under async method that too lie inside await lock anonymous block(?). I do async in task as Do Message is flooded with lot of calls simultaneously due to exposed part of a service.

I am assuming you are asking how to access the returned value from the task.
private async Task<string> RunMessageProces()
{
var statusProcess = "Your message successfully inserted in process queue.";
var retValue = await Task.Run(() =>
{
lock (_oQueue)
{
if (flagProcessing == true) //return when queue processing alredy started
{
return "Error"; // or some such error indicator
}
flagProcessing = true; //else start processing the queue till there are messages.
}
return string.Empty; // return a string here too....
});
// if( retValue == "Error" ) { return "Error" }
statusProcess = ProcessMyMessage();
return statusProcess;
}