public bool Create <T, R>(IEnumerable <T> items, Func <T, R> orderBy = null)
{
try
{
IOBoundary iob = IOBoundary.Create <T>();
IEnumerable <T> prev = iob.Read().Select(line => JsonConvert.DeserializeObject <T>(line));
items = prev.Concat(items);
if (orderBy != null)
{
items.OrderBy(orderBy);
}
IEnumerable <string> lines = items.Select(i => JsonConvert.SerializeObject(i));
iob.Write(lines);
return(true);
}
catch (Exception e)
{
if (Program.Employee == 2)
{
Console.WriteLine(e.Message);
}
return(false);
}
}
public IEnumerable <T> Delete <T>(Func <T, bool> filter = null)
{
try
{
IOBoundary iob = IOBoundary.Create <T>();
IEnumerable <T> prev, toSave, toDelete;
prev = iob.Read().Select(line => JsonConvert.DeserializeObject <T>(line));
if (filter != null)
{
toSave = prev.Where(p => !filter(p));
toDelete = prev.Where(p => filter(p));
}
else
{
toDelete = prev;
toSave = Enumerable.Empty <T>();
}
IEnumerable <string> lines = toSave.Select(t => JsonConvert.SerializeObject(t));
iob.Write(lines);
return(toDelete);
}
catch (Exception e)
{
if (Program.Employee == 2)
{
Console.WriteLine(e.Message);
}
return(Enumerable.Empty <T>());
}
}
public bool Update <T>(Func <T, T> update, Func <T, bool> filter = null)
{
try
{
IOBoundary iob = IOBoundary.Create <T>();
IEnumerable <T> prev, toUpdate;
prev = iob.Read().Select(line => JsonConvert.DeserializeObject <T>(line));
if (filter != null)
{
toUpdate = prev.Where(p => filter(p));
prev = prev.Where(p => !filter(p));
}
else
{
toUpdate = prev;
prev = Enumerable.Empty <T>();
}
IEnumerable <T> updated = toUpdate.Select(update).ToArray();
IEnumerable <string> lines = prev.Concat(updated).Select(x => JsonConvert.SerializeObject(x));
iob.Write(lines);
return(true);
}
catch (Exception e)
{
if (Program.Employee == 2)
{
Console.WriteLine(e.Message);
}
return(false);
}
}