/// <summary>
/// Load answer sheet data based on the user-chosen filter and show it.
/// </summary>
private void PopulateDataView()
{
var answerSheetSelector = CreateSelector();
dataView.Rows.Clear();
using (var db = new KlokanDBContext())
{
var answerSheetQuery = db.AnswerSheets.Where(answerSheetSelector);
foreach (var answerSheet in answerSheetQuery)
{
dataView.Rows.Add(answerSheet.AnswerSheetId, answerSheet.StudentNumber, answerSheet.Instance.Year, answerSheet.Instance.Category, answerSheet.Points);
}
}
}
/// <summary>
/// Load answer sheet data based on the selector and output it.
/// </summary>
private void ExportSelection(StreamWriter sw, Expression <Func <KlokanDBAnswerSheet, bool> > answerSheetSelector)
{
OutputHeader(sw);
using (var db = new KlokanDBContext())
{
// find the suitable answer sheets
var answerSheetQuery = db.AnswerSheets.Where(answerSheetSelector);
// select everything from them except for scans
var answerSheetSelectionQuery = from answerSheet in answerSheetQuery
select new AnswerSheetSelection
{
AnswerSheetId = answerSheet.AnswerSheetId,
StudentNumber = answerSheet.StudentNumber,
Points = answerSheet.Points,
Instance = answerSheet.Instance,
ChosenAnswers = answerSheet.ChosenAnswers
};
OutputAnswerSheetSelection(sw, answerSheetSelectionQuery);
}
}
/// <summary>
/// Extract answer sheet data from the database and display it in the form.
/// Returns false if data could not be loaded.
/// </summary>
private bool PopulateForm()
{
using (var db = new KlokanDBContext())
{
// load sheet data
var sheetQuery = from sheet in db.AnswerSheets
where sheet.AnswerSheetId == answerSheetId
select sheet;
KlokanDBAnswerSheet answerSheet = sheetQuery.FirstOrDefault();
if (answerSheet == null)
{
MessageBox.Show(Properties.Resources.ErrorTextSheetNotFoundInDatabase, Properties.Resources.ErrorCaptionGeneral,
MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
var instanceQuery = from instance in db.Instances
where instance.InstanceId == answerSheet.InstanceId
select instance;
KlokanDBInstance currentInstance = instanceQuery.FirstOrDefault();
if (answerSheet == null)
{
MessageBox.Show(Properties.Resources.ErrorTextSheetNotFoundInDatabase, Properties.Resources.ErrorCaptionGeneral,
MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
studentNumber = answerSheet.StudentNumber;
// show sheet data
studentNumberValueLabel.Text = answerSheet.StudentNumber.ToString();
idValueLabel.Text = answerSheet.AnswerSheetId.ToString();
yearValueLabel.Text = currentInstance.Year.ToString();
categoryValueLabel.Text = currentInstance.Category.ToString();
pointsValueLabel.Text = answerSheet.Points.ToString();
// load scan
scanPictureBox.Image = ImageHandling.GetBitmap(answerSheet.Scan);
// load answers and draw them
var chosenAnswersQuery = from chosenAnswer in db.ChosenAnswers
where chosenAnswer.AnswerSheetId == answerSheetId
select chosenAnswer;
var chosenAnswersList = chosenAnswersQuery.ToList();
if (chosenAnswersList.Count == 0)
{
MessageBox.Show(Properties.Resources.ErrorTextSheetNotFoundInDatabase, Properties.Resources.ErrorCaptionGeneral,
MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
TableArrayHandling.DbSetToAnswers(chosenAnswersList, out chosenAnswers);
FormTableHandling.DrawAnswers(table1PictureBox, chosenAnswers, 0, FormTableHandling.DrawCross, Color.Black);
FormTableHandling.DrawAnswers(table2PictureBox, chosenAnswers, 1, FormTableHandling.DrawCross, Color.Black);
FormTableHandling.DrawAnswers(table3PictureBox, chosenAnswers, 2, FormTableHandling.DrawCross, Color.Black);
var correctAnswersQuery = from correctAnswer in db.CorrectAnswers
where correctAnswer.InstanceId == answerSheet.InstanceId
select correctAnswer;
var correctAnswersList = correctAnswersQuery.ToList();
if (correctAnswersList.Count == 0)
{
MessageBox.Show(Properties.Resources.ErrorTextSheetNotFoundInDatabase, Properties.Resources.ErrorCaptionGeneral,
MessageBoxButtons.OK, MessageBoxIcon.Error);
return(false);
}
TableArrayHandling.DbSetToAnswers(correctAnswersQuery.ToList(), out correctAnswers);
FormTableHandling.DrawAnswers(table1PictureBox, correctAnswers, 0, FormTableHandling.DrawCircle, Color.Red);
FormTableHandling.DrawAnswers(table2PictureBox, correctAnswers, 1, FormTableHandling.DrawCircle, Color.Red);
FormTableHandling.DrawAnswers(table3PictureBox, correctAnswers, 2, FormTableHandling.DrawCircle, Color.Red);
}
return(true);
}
private void updateDatabaseButton_Click(object sender, EventArgs e)
{
updateDatabaseButton.Enabled = false;
var dialogResult = MessageBox.Show(Properties.Resources.PromptTextDatabaseUpdate, Properties.Resources.PromptCaptionDatabaseUpdate,
MessageBoxButtons.YesNo, MessageBoxIcon.Question);
if (dialogResult == DialogResult.No)
{
return;
}
// convert the chosen answers into a DbSet
List <KlokanDBChosenAnswer> newChosenAnswers = new List <KlokanDBChosenAnswer>();
for (int i = 0; i < 3; i++)
{
newChosenAnswers.AddRange(TableArrayHandling.AnswersToDbSet <KlokanDBChosenAnswer>(chosenAnswers, i, false));
}
int newPoints = points;
using (var db = new KlokanDBContext())
{
var query = from sheet in db.AnswerSheets
where sheet.AnswerSheetId == answerSheetId
select sheet;
KlokanDBAnswerSheet answerSheet = query.FirstOrDefault();
if (answerSheet == null)
{
MessageBox.Show(Properties.Resources.ErrorTextSheetNotFoundInDatabase, Properties.Resources.ErrorCaptionGeneral,
MessageBoxButtons.OK, MessageBoxIcon.Error);
return;
}
// load the old chosen answers so that EF knows it should delete them when the old answer sheet is deleted
List <KlokanDBChosenAnswer> blah = new List <KlokanDBChosenAnswer>(answerSheet.ChosenAnswers);
KlokanDBAnswerSheet updatedAnswerSheet = new KlokanDBAnswerSheet
{
StudentNumber = studentNumber,
Points = newPoints,
Scan = answerSheet.Scan,
InstanceId = answerSheet.InstanceId,
Instance = answerSheet.Instance,
ChosenAnswers = newChosenAnswers
};
db.AnswerSheets.Remove(answerSheet);
db.AnswerSheets.Add(updatedAnswerSheet);
try
{
db.SaveChanges();
MessageBox.Show(Properties.Resources.InfoTextDatabaseUpdated, Properties.Resources.InfoCaptionDatabaseUpdated,
MessageBoxButtons.OK, MessageBoxIcon.Information);
}
catch (Exception ex) when(ex is DbUpdateException || ex is DbUpdateConcurrencyException)
{
MessageBox.Show(Properties.Resources.ErrorTextDatabase, Properties.Resources.ErrorCaptionGeneral, MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
}
/// <summary>
/// Asynchronously stores results into a database described by KlokanDBContext.
/// Instances that already exist in the database are rewritten.
/// </summary>
/// <param name="results">Any enumerable structure of evaluation results.</param>
/// <returns>A void task.</returns>
async Task OutputResultsDB(IEnumerable <Result> results)
{
using (var db = new KlokanDBContext())
{
foreach (var result in results)
{
if (result.Error == true)
{
failedSheets++;
continue;
}
// find out if the instance this result belongs to is new or if it already exists
var query = from instance
in db.Instances
where instance.Year == result.Year && instance.Category == result.Category
select instance;
KlokanDBInstance currentInstance = query.FirstOrDefault();
// if the instance isn't saved in the database
if (currentInstance == default(KlokanDBInstance))
{
// try to search locally too (maybe the instance was added in the previous loop cycle)
var querylocal = from instance
in db.Instances.Local
where instance.Year == result.Year && instance.Category == result.Category
select instance;
currentInstance = querylocal.FirstOrDefault();
}
else
{
// remove it completely because the new one will rewrite it
// lazy loading is used, so we need to load all the relations of an instance if we want Remove() to remove those as well
var blah = currentInstance.AnswerSheets;
var blah2 = currentInstance.CorrectAnswers;
List <ICollection <KlokanDBChosenAnswer> > blah3 = new List <ICollection <KlokanDBChosenAnswer> >();
foreach (var answerSheetBlah in blah)
{
blah3.Add(answerSheetBlah.ChosenAnswers);
}
db.Instances.Remove(currentInstance);
await db.SaveChangesAsync(progressDialog.GetCancellationToken());
currentInstance = null;
}
// if the instance doesn't exist locally either
if (currentInstance == default(KlokanDBInstance))
{
List <KlokanDBCorrectAnswer> correctAnswers = new List <KlokanDBCorrectAnswer>();
for (int i = 0; i < 3; i++)
{
correctAnswers.AddRange(TableArrayHandling.AnswersToDbSet <KlokanDBCorrectAnswer>(result.CorrectAnswers, i, false));
}
currentInstance = new KlokanDBInstance
{
Year = result.Year,
Category = result.Category,
CorrectAnswers = correctAnswers
};
db.Instances.Add(currentInstance);
}
List <KlokanDBChosenAnswer> chosenAnswers = new List <KlokanDBChosenAnswer>();
for (int i = 0; i < 3; i++)
{
chosenAnswers.AddRange(TableArrayHandling.AnswersToDbSet <KlokanDBChosenAnswer>(result.ChosenAnswers, i, false));
}
var answerSheet = new KlokanDBAnswerSheet
{
StudentNumber = result.StudentNumber,
Points = result.Score,
ChosenAnswers = chosenAnswers,
Scan = ImageHandling.GetImageBytes(result.SheetFilename, ImageFormat.Png)
};
currentInstance.AnswerSheets.Add(answerSheet);
}
await db.SaveChangesAsync(progressDialog.GetCancellationToken());
}
}
