mORMot Open Source

macfly

Member

From: Brasil

Registered: 2016-08-20

Posts: 374

Safe way to verify that the child record has been instantiated

TTestChild = class(TSqlrecord)..

Ttest = class(TSqlrecord)
published
  ...
  Child : TTestChild read FChild write FChild;
end;

//Retrieve child if exists
if ATest.Child <> nil then
begin
   ATest.Child := TTestChild.Create(Database, ATest.Child);
   Log(ATest.Child.Name);
end;

But now, how i test if child is retrevied to avoid to retrieve again?

And ATest.Child assigned with this form is freed when ATest is freed?

ab

Administrator

From: France

Registered: 2010-06-21

Posts: 14,667

Website

Re: Safe way to verify that the child record has been instantiated

It depends on how the TTest class instance is created.

See http://synopse.info/files/html/Synopse% … ml#TITL_70

If you use CreateJoined, it will create the instance for you.

But IMHO the safest approach is to define a TID published property, and use a public property with a getter to create a TTestChild local instance.