TObject: what changed

Revision 0 to 1. Removed lines have a minus sign; added lines have a plus sign.

Title: TObject

New		Line
1	+	`TObject` is the base [[Class\|class]] for any other `class`, whether you declare it or not. It provides only some very generic [[Method\|methods]], mostly [[virtual]]. The rationale for `TObject` is that in [[Object Pascal]] every `class` must be derived from another, `TObject` being the exception that ends the derivation chain.
2	+
3	+	The [[Constructor\|constructor]] `TObject.Create()`, inherited by every other `class` by default, can be hidden declaring another `constructor` with the same name in the derived `class`, with or without parameters. This come handy implementing the [[Singleton pattern]].
4	+
5	+	``` pascal
6	+	{ Defined in objpash.inc }
7	+
8	+	constructor Create;
9	+	destructor Destroy; virtual;
10	+	class function newinstance : tobject; virtual;
11	+	procedure CleanupInstance;
12	+	procedure FreeInstance; virtual;
13	+
14	+	function SafeCallException(exceptobject : tobject; exceptaddr : codepointer) : HResult; virtual;
15	+	procedure DefaultHandler(var message);virtual;
16	+	procedure Free;
17	+
18	+	class function InitInstance(instance : pointer) : tobject;
19	+	class function ClassType : tclass;
20	+	class function ClassInfo : pointer;
21	+	class function ClassName : shortstring;
22	+	class function ClassNameIs(const name : string) : boolean;
23	+	class function ClassParent : tclass;
24	+	class function InstanceSize : SizeInt;
25	+	class function InheritsFrom(aclass : tclass) : boolean;
26	+	class function StringMessageTable : pstringmessagetable;
27	+	class function MethodAddress(const name : shortstring) : codepointer;
28	+	class function MethodName(address : codepointer) : shortstring;
29	+	function FieldAddress(const name : shortstring) : pointer;
30	+
31	+	procedure AfterConstruction;virtual;
32	+	procedure BeforeDestruction;virtual;
33	+
34	+	procedure DefaultHandlerStr(var message);virtual;
35	+
36	+	procedure Dispatch(var message);virtual;
37	+	procedure DispatchStr(var message);virtual;
38	+
39	+	function GetInterface(const iid : tguid; out obj) : boolean;
40	+	function GetInterface(const iidstr : shortstring;out obj) : boolean;
41	+	function GetInterfaceByStr(const iidstr : shortstring; out obj) : boolean;
42	+	function GetInterfaceWeak(const iid : tguid; out obj) : boolean;
43	+
44	+	class function GetInterfaceEntry(const iid : tguid) : pinterfaceentry;
45	+	class function GetInterfaceEntryByStr(const iidstr : shortstring) : pinterfaceentry;
46	+	class function GetInterfaceTable : pinterfacetable;
47	+
48	+	class function UnitName : ansistring;
49	+	function Equals(Obj: TObject) : boolean; virtual;
50	+	function GetHashCode: PtrInt; virtual;
51	+	function ToString: ansistring; virtual;
52	+	```
53	+
54	+	---
55	+	From the Free Pascal wiki, page "TObject", as it stood on 2019-11-13 after a change by Djzepi, out of the wiki's dump of 2024-05-26. Copyright stays with the author who wrote it, according to the old wiki's [[Licensing]] page. If you have concerns about this material, [message the admin](/wiki-contact).

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