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GetObjectProp function

In unit TypInfo

Return value of an object-type property.

Declaration

pascal
function GetObjectProp(Instance: TObject; const PropName: string)
: TObject

Description

GetObjectProp returns the object which the property described by PropInfo with name Propname points to for object Instance.

If MinClass is specified, then if the object is not descendent of class MinClass, then Nil is returned.

Errors

No checking is done whether Instance is non-nil, or whether PropInfo describes a valid method property of Instance. Specifying an invalid property name in PropName will result in an EPropertyError exception.

See also

Example: ex5

pascal
program example5;

{ This program demonstrates the GetObjectProp function }

{$mode objfpc}

uses rttiobj,typinfo;

Var
  O : TMyTestObject;
  PI : PPropInfo;
  NO1,NO2 : TNamedObject;

begin
  O:=TMyTestObject.Create;
  NO1:=TNamedObject.Create;
  NO1.ObjectName:='First named object';
  NO2:=TNamedObject.Create;
  NO2.ObjectName:='Second named object';
  O.ObjField:=NO1;
  Writeln('Object property : ');
  PI:=GetPropInfo(O,'ObjField');
  Write('Property class     : ');
  Writeln(GetObjectPropClass(O,'ObjField').ClassName);
  Write('Value              : ');
  Writeln((O.ObjField as TNamedObject).ObjectName);
  Write('Get (name)         : ');
  Writeln((GetObjectProp(O,'ObjField') As TNamedObject).ObjectName);
  Write('Get (propinfo)     : ');
  Writeln((GetObjectProp(O,PI,TObject) as TNamedObject).ObjectName);
  SetObjectProp(O,'ObjField',NO2);
  Write('Set (name,NO2)     : ');
  Writeln((O.ObjField as TNamedObject).ObjectName);
  SetObjectProp(O,PI,NO1);
  Write('Set (propinfo,NO1) : ');
  Writeln((O.ObjField as TNamedObject).ObjectName);
  O.Free;
end.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.