You are here: All articles » Programming » Delphi generics
-
Delphi generics
written: 13 years ago
category: Programming
Previous
Next
Just found a wonderful and deep look into generics, anonymous routines and routine references here . Written by Sébastien Doeraene.
Generics were introduced in Delphi 2009, and I'm a big fan of them, as they help me do less type casting on TObjectList's items for example.
Want to know how sorting a TObjectList<TWhatever> works? Here's how it works:
type TDBObject = class Name: String; end; TDBObjectList = TObjectList<TDBObject>; TDBObjectComparer = class(TComparer<TDBObject>) function Compare(const Left, Right: TDBObject): Integer; override; end; procedure TMainform.btnOkClick(Sender: TObject); var o: TDBObject; begin Result := TDBObjectList.Create(TDBObjectComparer.Create); o := TDBObject.Create; o.Name := 'foo'; Result.Add(o); o := TDBObject.Create; o.Name := 'bar'; Result.Add(o); end; function TDBObjectComparer.Compare(const Left, Right: TDBObject): Integer; begin Result := CompareText(Left.Name, Right.Name); end;
ftp://ftp-developpez.com/sjrd/tutoriels/delphi-generics/delphi-generics.pdf
Leave a comment