GetObjectProp
Return value of an object-type property.
Declaration
Source position: typinfo.pp line 933
function GetObjectProp(Instance: TObject; const PropName: string)
: TObject;
function GetObjectProp(Instance: TObject; const PropName: string;
MinClass: TClass) : TObject;
function GetObjectProp(Instance: TObject; PropInfo: PPropInfo) : TObject;
function GetObjectProp(Instance: TObject; PropInfo: PPropInfo;
MinClass: TClass) : 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
| Name | Description |
|---|---|
| GetEnumProp | Return the value of an enumeration type property. |
| GetFloatProp | Return value of floating point property |
| GetInt64Prop | return value of an Int64 property |
| GetObjectProp | Return value of an object-type property. |
| GetOrdProp | Get the value of an ordinal property |
| GetSetProp | Return the value of a set property. |
| GetStrProp | Return the value of a string property. |
| SetMethodProp | Set the value of a method property |
Example
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.