Get/Set sub properties ussing RTTI

Question

Given the following code snippet below, using GetPropValue(MyComponent,\'MySubComponent.Prop1\') raises an EPropertyError exception. How can I retrieve or set t

Answer 1

The dot notation you used in your question is not supported.

You need to get the Value of the SubComponent, then perform the Set and Get on the individual properties.

var
  C: TRttiContext;
  MyComp : TMyComponent;
  MyCompType : TRttiInstanceType;
  MySubCompType : TRttiInstanceType;
  MySubComponentValue : TValue;
begin
  MyComp := TMyComponent.create(Self); 
  ...
  // RTTI.Pas Method
  MyCompType :=  c.GetType(TMyComponent.ClassInfo) as TRttiInstanceType;
  MySubCompType := c.GetType(TMySubComponent.ClassInfo) as TRttiInstanceType;
  MySubComponentValue := MyCompType.GetProperty('MySubComponent').GetValue(MyComp);

  if Not MySubComponentValue.IsEmpty then
  begin
      MySubCompType.GetProperty('Prop1').SetValue(MySubComponentValue.AsObject,43);
  end;

 //TypInfo.pas Method
 SubComp := GetObjectProp(MyComp,'MySubComponent');
 if Assigned(SubComp) then
 begin
    SetPropValue(SubComp,'Prop1',5);
    prop1Value := GetPropValue(SubComp,'Prop1');
 end;

end;

The TypInfo.pas method will only work with published properties, you can get the public properties with the RTTI.pas method.