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I’m working on a class TMethodsInjector that uses RTTI to inject a method into a method-type property (like events). If a method is already assigned, I want to combine it with the new one (same signature) and assign the result. The key part is here: if not Assigned(LOldMethod.Code) then LCombined := LNewMethod else LCombined := GenerateCombinedMethod(LRttiProperty, LOldMethod, LNewMethod); I need help implementing GenerateCombinedMethod — it should dynamically wrap both LOldMethod and LNewMethod (same structure) into a single TMethod that invokes both in order. Is there a clean way to do this using RTTI, without knowing the method signature in advance? my full class code is: unit API.Methods.Injector; interface uses System.Classes, System.SysUtils, System.Rtti, System.TypInfo; type TMethodsInjector = class public class procedure InjectMethod(aTarget: TObject; const aPropertyName: string; aMethodAddress: Pointer; aMethodData: TObject); static; end; implementation { TMethodsInjector } class procedure TMethodsInjector.InjectMethod(aTarget: TObject; const aPropertyName: string; aMethodAddress: Pointer; aMethodData: TObject); var LRttiContext: TRttiContext; LRttiType: TRttiType; LRttiProperty: TRttiProperty; LOldMethod, LNewMethod, LCombined: TMethod; begin if not Assigned(aTarget) then Exit; LRttiContext := TRttiContext.Create; try LRttiType := LRttiContext.GetType(aTarget.ClassType); LRttiProperty := LRttiType.GetProperty(aPropertyName); if Assigned(LRttiProperty) and (LRttiProperty.PropertyType.TypeKind = tkMethod) then begin LOldMethod := GetMethodProp(aTarget, aPropertyName); LNewMethod.Code := aMethodAddress; LNewMethod.Data := aMethodData; if not Assigned(LOldMethod.Code) then LCombined := LNewMethod else LCombined := GenerateCombinedMethod(LRttiProperty, LOldMethod, LNewMethod); SetMethodProp(aTarget, aPropertyName, LCombined); end else raise Exception.CreateFmt('Property %s not found or is not a method on %s', [aPropertyName, aTarget.ClassName]); finally LRttiContext.Free; end; end; end.