Question

The setup is pretty standard. Created a view and also the repository with the SQL Server connection string. Passed the repository the view model and on the view model’s constructor I call a collection from the repository. It was all working fine until I tried to do it asynchronously using the async/await combo but now I get the error “The context cannot be used while the model is being created” when calling the repository’s collection.

Old working code:

void FillPeopleList()
{
  PeopleList = _repository.GetPeople();
}

New broken code:

async void FillPeopleList()
{
  await Task.Run(()=>
  {
    PeopleList = _repository.GetPeople(); // Error
  });
}

Answer 1

EF is not thread-safe.

You cannot use the same context on multiple threads.