public async Task <IActionResult> Create(
DepartmentAddEditDto department, [FromServices] IDepartmentService service)
{
if (ModelState.IsValid)
{
try
{
await service.CreateDepartmentAndSaveAsync(department);
TempData["Message"] = Constants.SUCCESS_MESSAGE;
return(RedirectToAction(nameof(Index)));
}
catch (Exception ex)
{
ViewBag.HasError = true;
ViewBag.Message = ex.Message;
}
}
await PopulateInstructorsDropDownListAsync(service, department.InstructorId);
return(View($"{_viewFolder}Create.cshtml", department));
}
public async Task <int> CreateDepartmentAndSaveAsync(DepartmentAddEditDto dto)
{
int result;
try
{
_context.Add(new Department {
DepartmentId = dto.DepartmentId,
Budget = dto.Budget,
InstructorId = dto.InstructorId,
Name = dto.Name,
StartDate = dto.StartDate,
RowVersion = dto.RowVersion
});
result = await _context.SaveChangesAsync();
}
catch (Exception ex)
{
_logger.LogError(ex, $"Failed to create new Department: {dto}");
throw ex;
}
return(result);
}
public async Task <IActionResult> Edit(
int?id, byte[] rowVersion, DepartmentAddEditDto department, [FromServices] IDepartmentService service)
{
if (!id.HasValue ||
id.Value != department.DepartmentId)
{
return(NotFound());
}
if (ModelState.IsValid)
{
try
{
await service.UpdateDepartmentAndSaveAsync(department, rowVersion);
TempData["Message"] = Constants.SUCCESS_MESSAGE;
return(RedirectToAction(nameof(Index)));
}
catch (GeneralException ex)
{
ViewBag.HasError = true;
ViewBag.Message = ex.Message;
ModelState.Remove("RowVersion");
}
catch (Exception ex)
{
ViewBag.HasError = true;
ViewBag.Message = Constants.ERROR_MESSAGE_STANDARD + ": " + ex.Message;
ModelState.Remove("RowVersion");
}
}
await PopulateInstructorsDropDownListAsync(service, department.InstructorId);
return(View($"{_viewFolder}Edit.cshtml", department));
}
public async Task <int> UpdateDepartmentAndSaveAsync(DepartmentAddEditDto dto, byte[] rowVersion)
{
var result = 0;
try
{
var departmentToUpdate = await _context.Departments
.FirstOrDefaultAsync(m => m.DepartmentId == dto.DepartmentId);
if (departmentToUpdate == null)
{
var errMsg = $"Record does not exist or has been deleted for DepartmentId={dto.DepartmentId}";
_logger.LogError("", errMsg);
throw new GeneralException(errMsg);
}
_context.Entry(departmentToUpdate).Property("RowVersion").OriginalValue = rowVersion;
departmentToUpdate.Budget = dto.Budget;
departmentToUpdate.InstructorId = dto.InstructorId;
departmentToUpdate.Name = dto.Name;
departmentToUpdate.StartDate = dto.StartDate;
// Comment out this line to enable updating only the fields with changed values
//_context.Departments.Update(courseInDb);
result = await _context.SaveChangesAsync();
}
catch (DbUpdateConcurrencyException ex)
{
var exceptionEntry = ex.Entries.Single();
var userValues = (Department)exceptionEntry.Entity;
var dbEntry = exceptionEntry.GetDatabaseValues();
var errMsg = "";
if (dbEntry == null)
{
errMsg = "Unable to save changes. The department was deleted by another user.";
throw new GeneralException(errMsg);
}
else
{
var dbValues = (Department)dbEntry.ToObject();
if (dbValues.Name != userValues.Name)
{
errMsg += $"<li>Conflict field \"Name\": New value is \"{dbValues.Name}\"</li>";
}
if (dbValues.Budget != userValues.Budget)
{
errMsg += $"<li>Conflict field \"Budget\": New value is \"{dbValues.Budget:c}\"</li>";
}
if (dbValues.StartDate != userValues.StartDate)
{
errMsg += $"<li>Conflict field \"StartDate\": New value is \"{dbValues.StartDate:d}\"</li>";
}
if (dbValues.InstructorId != userValues.InstructorId)
{
Instructor dbInstructor = await _context.Instructors
.FirstOrDefaultAsync(i => i.InstructorId == dbValues.InstructorId);
errMsg += $"<li>Conflict field \"Administrator\": New value is \"{dbInstructor?.FullName}\"</li>";
}
errMsg = "The record you attempted to edit "
+ "was modified by another user after you got the original value."
+ "<br><br>The edit operation was canceled and the new values in the database displayed as below:"
+ "<ul>" + errMsg + "</ul>"
+ "<br>If you still intend to edit this record, click "
+ "the \"Save\" button again. Otherwise click the \"Back to List\".";
dto.RowVersion = (byte[])dbValues.RowVersion;
throw new GeneralException(errMsg);
}
}
catch (Exception ex)
{
_logger.LogError(ex, $"Failed to update Department: {dto}");
throw ex;
}
return(result);
}