Delphi RTTI: Get property's class - delphi

Question

Using Delphi 2010 and RTTI, I know how to get the class type of an object and how to get/set the value and type of an object's properties, but how do you determine which class in the inheritance chain a property came from? I want to use the properties of a base class differently than the main class.
Consider this code:
TClassBase = class(TObject)
published
property A: Integer;
end;
TClassDescendant = class(TClassBase)
published
property B: Integer;
end;
procedure CheckProperties(Obj: TObject);
var
ctx: TRttiContext;
objType: TRttiType;
Prop: TRttiProperty;
begin
ctx := TRttiContext.Create;
objType := ctx.GetType(Obj.ClassInfo);
for Prop in objType.GetProperties do begin
if Prop.GetClassType is TClassBase then
// do something special with base class properties
else
// standard functionality on all other properties
end;
end;
The problem is there is no GetClassType for the properties. ClassType just returns TRttiInstancePropertyEx instead of the name of the class to which the property belongs.

Answer 1

Another option is use the Parent property of the TRttiProperty, from here you can access to the class which the property is part of.
{$APPTYPE CONSOLE}
{$R *.res}
uses
Rtti,
SysUtils;
type
TClassBase = class(TObject)
private
FA: Integer;
published
property A: Integer read FA;
end;
TClassDescendant = class(TClassBase)
private
FB: Integer;
published
property B: Integer read FB;
end;
procedure CheckProperties(Obj: TObject);
var
ctx: TRttiContext;
objType: TRttiType;
Prop: TRttiProperty;
begin
ctx := TRttiContext.Create;
objType := ctx.GetType(Obj.ClassInfo);
for Prop in objType.GetProperties do
if TRttiInstanceType(Prop.Parent).MetaclassType=TClassBase then
Writeln(Format('The property %s is declarated in the TClassBase class',[Prop.Name]))
else
Writeln(Format('The property %s is not declarated in the TClassBase class',[Prop.Name]))
end;
begin
try
//CheckProperties(TClassBase.Create);
CheckProperties(TClassDescendant.Create);
except
on E: Exception do
Writeln(E.ClassName, ': ', E.Message);
end;
Readln;
end.

Answer 2

I don't know if it's possible to get the class which a property was introduced, but you can solve your problem with regular RTTI:
begin
...
for Prop in objType.GetProperties do begin
if Assigned(GetPropInfo(TClassBase, Prop.Name)) then
// do something special with base class properties
else
// standard functionality on all other properties
end;
end;

Answer 3

You can use the GetDeclaredProperties method to get properties declarated in the current class and then compare against the values returned by the GetProperties method.
Try this sample.
{$APPTYPE CONSOLE}
{$R *.res}
uses
Rtti,
SysUtils;
type
TClassBase = class(TObject)
private
FA: Integer;
published
property A: Integer read FA;
end;
TClassDescendant = class(TClassBase)
private
FB: Integer;
published
property B: Integer read FB;
end;
procedure CheckProperties(Obj: TObject);
function ExistProp(const PropName:string; List:TArray<TRttiProperty>) : Boolean;
var
Prop: TRttiProperty;
begin
result:=False;
for Prop in List do
if SameText(PropName, Prop.Name) then
begin
Result:=True;
break;
end;
end;
var
ctx: TRttiContext;
objType: TRttiType;
Prop: TRttiProperty;
CurrentClassProps : TArray<TRttiProperty>;
begin
ctx := TRttiContext.Create;
objType := ctx.GetType(Obj.ClassInfo);
CurrentClassProps:=objType.GetDeclaredProperties;
for Prop in objType.GetProperties do
if ExistProp(Prop.Name, CurrentClassProps) then
Writeln(Format('The property %s is declarated in the current %s class',[Prop.Name, obj.ClassName]))
else
Writeln(Format('The property %s is declarated in the base class',[Prop.Name]))
end;
begin
try
//CheckProperties(TClassBase.Create);
CheckProperties(TClassDescendant.Create);
except
on E: Exception do
Writeln(E.ClassName, ': ', E.Message);
end;
Readln;
end.