protected static void PreviewKeyDown(object eventArgs)
{
var tempEventArgs = (object[])eventArgs;
if (!(tempEventArgs[0] is KeyEventArgs e && tempEventArgs[1] is DataGrid sender))
{
throw new ArgumentException("Bad arguments in PreviewKeyDown");
}
switch (e.Key)
{
case Key.Escape:
sender.CancelEdit();
sender.CancelEdit();
return;
case Key.Delete:
if (!(sender.SelectedItem is TEntity entity))
{
return;
}
using (var context = new BookOrdersContext()) {
try {
PropertyInfo property =
context.GetType().GetProperty(typeof(TEntity).Name.Replace("And", "sAnd") + 's');
if (property != null)
{
((DbSet <TEntity>)property.GetValue(context)).Attach(entity);
((DbSet <TEntity>)property.GetValue(context)).Remove(entity);
}
context.SaveChanges();
} catch (DbUpdateException exception) {
if (!(exception.InnerException is UpdateException innerException))
{
throw;
}
if (!(innerException.InnerException is Npgsql.PostgresException innerInnerException))
{
throw;
}
if (innerInnerException.SqlState == "23503")
{
MessageBox.Show(innerInnerException.MessageText,
"Error", MessageBoxButton.OK, MessageBoxImage.Error);
e.Handled = true;
}
else
{
throw;
}
}
}
return;
}
}
protected static void DataGridRowEditEnding(object eventArgs)
{
var tempEventArgs = (object[])eventArgs;
if (!(tempEventArgs[0] is DataGridRowEditEndingEventArgs e && tempEventArgs[1] is DataGrid sender))
{
throw new ArgumentException("Bad arguments in PreviewKeyDown");
}
if (e.EditAction == DataGridEditAction.Cancel || !(e.Row.Item is TEntity entity) ||
!entity.Validator.IsValid ||
!entity.IsDirty)
{
return;
}
using (var context = new BookOrdersContext()) {
try {
if (e.Row.IsNewItem)
{
PropertyInfo property =
context.GetType().GetProperty(typeof(TEntity).Name.Replace("And", "sAnd") + 's');
if (property != null)
{
((DbSet <TEntity>)property.GetValue(context)).Add(entity);
}
}
else
{
context.Entry(entity).State = EntityState.Modified;
}
context.SaveChanges();
} catch (Exception exception) {
sender.CancelEdit();
sender.CancelEdit();
Exception innerException = exception;
while (innerException?.InnerException != null)
{
innerException = innerException.InnerException;
}
MessageBox.Show(innerException?.Message, "Error", MessageBoxButton.OK, MessageBoxImage.Error);
}
}
}
