/// <summary>
/// Gets data from the scan item field and shows it.
/// </summary>
private void PopulateForm()
{
// load scan
scanPictureBox.Image = ImageHandling.GetBitmap(scanItem.Image);
// load the answers
List <KlokanTestDBExpectedAnswer> expectedValues = new List <KlokanTestDBExpectedAnswer>(scanItem.ExpectedValues);
TableArrayHandling.DbSetToAnswers(expectedValues, out expectedValuesStudentTable, out expectedValuesAnswerTable);
FormTableHandling.DrawAnswers(studentTablePictureBox, expectedValuesStudentTable, 0, FormTableHandling.DrawCross, Color.Black);
FormTableHandling.DrawAnswers(answerTable1PictureBox, expectedValuesAnswerTable, 0, FormTableHandling.DrawCross, Color.Black);
FormTableHandling.DrawAnswers(answerTable2PictureBox, expectedValuesAnswerTable, 1, FormTableHandling.DrawCross, Color.Black);
FormTableHandling.DrawAnswers(answerTable3PictureBox, expectedValuesAnswerTable, 2, FormTableHandling.DrawCross, Color.Black);
bool[,,] computedValuesStudentTable;
bool[,,] computedValuesAnswerTable;
List <KlokanTestDBComputedAnswer> computedValues = new List <KlokanTestDBComputedAnswer>(scanItem.ComputedValues);
TableArrayHandling.DbSetToAnswers(computedValues, out computedValuesStudentTable, out computedValuesAnswerTable);
FormTableHandling.DrawAnswers(studentTablePictureBox, computedValuesStudentTable, 0, FormTableHandling.DrawCircle, Color.Red);
FormTableHandling.DrawAnswers(answerTable1PictureBox, computedValuesAnswerTable, 0, FormTableHandling.DrawCircle, Color.Red);
FormTableHandling.DrawAnswers(answerTable2PictureBox, computedValuesAnswerTable, 1, FormTableHandling.DrawCircle, Color.Red);
FormTableHandling.DrawAnswers(answerTable3PictureBox, computedValuesAnswerTable, 2, FormTableHandling.DrawCircle, Color.Red);
}
private void updateButton_Click(object sender, EventArgs e)
{
var dialogResult = MessageBox.Show(Properties.Resources.PromptTextDatabaseUpdate, Properties.Resources.PromptCaptionDatabaseUpdate,
MessageBoxButtons.YesNo, MessageBoxIcon.Question);
if (dialogResult == DialogResult.No)
{
return;
}
updateButton.Enabled = false;
// prepare the DbSet of chosen expected answers
List <KlokanTestDBExpectedAnswer> expectedAnswers = new List <KlokanTestDBExpectedAnswer>();
expectedAnswers.AddRange(TableArrayHandling.AnswersToDbSet <KlokanTestDBExpectedAnswer>(expectedValuesStudentTable, 0, true));
for (int i = 0; i < 3; i++)
{
expectedAnswers.AddRange(TableArrayHandling.AnswersToDbSet <KlokanTestDBExpectedAnswer>(expectedValuesAnswerTable, i, false));
}
if (addMode)
{
scanItem.Image = ImageHandling.GetImageBytes(scanFilePath, ImageFormat.Png);
}
scanItem.ExpectedValues = expectedAnswers;
scanItem.Correctness = -1; // correctness will only have a valid value once the evaluation is run
using (var testDB = new KlokanTestDBContext())
{
// when editing an item we first have to delete the old one
if (!addMode)
{
var oldScanItemQuery = from scan in testDB.Scans
where scan.ScanId == scanItem.ScanId
select scan;
var oldExpectedAnswers = from answer in testDB.ExpectedValues
where answer.ScanId == scanItem.ScanId
select answer;
// delete the old expected answers
foreach (var answer in oldExpectedAnswers)
{
testDB.ExpectedValues.Remove(answer);
}
// assign new expected answers
var oldScanItem = oldScanItemQuery.FirstOrDefault();
oldScanItem.ExpectedValues = scanItem.ExpectedValues;
oldScanItem.Correctness = -1;
}
else
{
KlokanTestDBScan newScanItem = new KlokanTestDBScan
{
ExpectedValues = scanItem.ExpectedValues,
ComputedValues = scanItem.ComputedValues,
Image = scanItem.Image,
Correctness = -1
};
testDB.Scans.Add(newScanItem);
}
try
{
testDB.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);
}
}
PopulateForm();
}
/// <summary>
/// Uses a native library to load an image and extract answers from it.
/// Works with both image bytes as well as just an image file path.
/// This method is unsafe.
/// </summary>
/// <param name="sheet">The path to the image containing answers to be extracted as a string or an array of image bytes.</param>
/// <param name="studentNumberAnswers">This parameter will contain the student number answers extracted from the student number table.</param>
/// <param name="extractedAnswers">This parameter will contain the answers extracted from the answer tables.</param>
/// <returns>True if the process has succeeded and false otherwise.</returns>
bool ExtractAnswers <T>(T sheet, out bool[,,] studentNumberAnswers, out bool[,,] extractedAnswers)
{
extractedAnswers = new bool[3, 8, 5];
studentNumberAnswers = new bool[1, 5, 10];
// the first row and the first column of the original tables were removed as they do not contain any answers
int studentNumberRows = parameters.StudentTableRows - 1;
int studentNumberColumns = parameters.StudentTableColumns - 1;
int answerRows = parameters.AnswerTableRows - 1;
int answerColumns = parameters.AnswerTableColumns - 1;
NumberWrapper numberWrapper = new NumberWrapper();
AnswerWrapper answerWrapper = new AnswerWrapper();
bool success = false;
unsafe
{
bool *numberPtr = numberWrapper.number;
bool *answersPtr = answerWrapper.answers;
bool *successPtr = &success;
string sheetFilename;
byte[] sheetImageBytes;
// if the sheet has been passed as a filename
if ((sheetFilename = sheet as string) != null)
{
NativeAPIWrapper.extract_answers_path_api(sheetFilename, parameters, numberPtr, answersPtr, successPtr);
}
// if the sheet has been passed as image bytes
else if ((sheetImageBytes = sheet as byte[]) != null)
{
// the image is saved in PNG (or another format) so we need to convert it to BMP which the library can read
Image sheetImage = ImageHandling.GetBitmap(sheetImageBytes);
int imageRows = sheetImage.Height;
int imageCols = sheetImage.Width;
byte[] sheetImageBitmapBytes = ImageHandling.GetImageBytes(sheetImage, ImageFormat.Bmp);
sheetImage.Dispose();
fixed(byte *imageBitmapBytesPtr = sheetImageBitmapBytes)
{
NativeAPIWrapper.extract_answers_image_api(imageBitmapBytesPtr, imageRows, imageCols, parameters, numberPtr, answersPtr, successPtr);
}
}
else
{
return(false);
}
if (!success)
{
return(false);
}
// convert the student number values from a C-style array of answers to a C# multi-dimensional array
for (int row = 0; row < studentNumberRows; row++)
{
for (int col = 0; col < studentNumberColumns; col++)
{
if (numberPtr[row * studentNumberColumns + col] == true)
{
studentNumberAnswers[0, row, col] = true;
}
else
{
studentNumberAnswers[0, row, col] = false;
}
}
}
// convert the answer table values from a C-style array to a C# multi-dimensional array
for (int table = 0; table < parameters.TableCount - 1; table++)
{
for (int row = 0; row < answerRows; row++)
{
for (int col = 0; col < answerColumns; col++)
{
if (answersPtr[table * answerRows * answerColumns + row * answerColumns + col] == true)
{
extractedAnswers[table, row, col] = true;
}
else
{
extractedAnswers[table, row, col] = false;
}
}
}
}
}
return(true);
}
/// <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);
}
/// <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());
}
}