Question

I have a silverlight mvvm with ria project. I have a UI in which admin users can enter info to create new work orders. However, I am having trouble calling the db and adding a new record to the table. I have no code-behind for the UI, the controls are tied to the model through Commands and Command Parameters. So when a user clicks, ‘Add new job’ it comes here,

public class EditJobViewModel : ViewModelBase
{
    private Job _job;

    public Job CurrentJob
    {
        get { return _job; }
        set
        {
            _job = value;
            OnPropertyChanged("CurrentJob");
        }
    }

    public ICommand NewJob
    {
        get
        {
            return new DelegateCommand(BeginNewJob, (o) => true);
        }

    }


    public void BeginNewJob(object o)
    {

            _job = new Job();
            //_job.JobNumber = _job.JobID.ToString();
            _job.AssignedTo = App.userID;
            _job.AddedBy = App.userID;
            _job.FileTypeJob = "PDF";
            _job.AddedTS = DateTime.Now;
            _job.OpenDate = DateTime.Now;
            BeginSave(o);
        }
    }

Where Im having trouble is creating a new record in the ‘Job’ table. On my breakpoint it returns all the columns it needs to, just not a new ‘JobID’ which is my primary key. This is how I was supposedly trying to create a new record.

public void BeginSave(object o)
    {
        if (!IsDesignTime)
        {
            try
            {
                if (CurrentJob.EntityState == EntityState.New)
                {
                    CurrentJob.AddedBy = App.userID;
                    CurrentJob.AddedTS = DateTime.Now;
                }
                CurrentJob.UpdatedBy = App.userID;
                CurrentJob.UpdatedTS = DateTime.Now;

                // This is here because of a bug in infragistics grid/Entity Framework 
                foreach (JobFileType ft in CurrentJob.JobFileTypes)
                {
                    if (ft.EntityState != EntityState.Unmodified)
                        (ft as IEditableObject).EndEdit();
                }

                foreach (JobTag tag in CurrentJob.JobTags)
                {
                    if (tag.EntityState != EntityState.Unmodified)
                        (tag as IEditableObject).EndEdit();
                }
                //(CurrentJob as IEditableObject).EndEdit();

                SubmitOperation s = _context.SubmitChanges();
                if (s.HasError)
                { }
            }
            catch (Exception ex)
            { }
        }
    }

Except that it never hits the EntityState.new. That’s just the way I thought to try it. Im thinking there a way to do it from the ‘BeginNewJob’ command but unable to find a way to create a new JobID or record in general. The Database already has 10000 records and has multiple users creating jobs, so I need a way to get the last job created (getMaxID()??) and increment appropriately, creating a new job on the spot.

Answer 1

İf you use guid type for id column, you will not need to find next id and this approach will decouple new objects from previous objects.