unit Unit2;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, EventHook, Vcl.StdCtrls, Rtti;

type
  TForm2 = class(TForm)
    Memo1: TMemo;
    procedure FormCreate(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form2: TForm2;
  NForm1, NForm2: TForm;

implementation

{$R *.dfm}

procedure TForm2.FormCreate(Sender: TObject);
begin
  NForm1 := TForm.Create(nil);
  NForm1.Name := 'MyForm1';
  NForm1.Show;
  NForm2 := TForm.Create(nil);
  NForm2.Name := 'MyForm2';
  NForm2.Show;

  HEventObj.ESet(NForm1, 'OnMouseDown'{, ['DopArgs TValue = ListDopArgs']});
  HEventObj.ESet(NForm2, 'OnMouseDown'{, ['DopArgs TValue = ListDopArgs']});

  HEventObj.OnBefore :=
      procedure(Base: TEventObject; Params: TArray<TValue>; ListDopArgs: TArrTypeAddInHook)
    var
      Str: string;
      V: TValue;
    begin
      Str := TComponent(Base.Sender).Name + ' =';

      for V in Params do
        Str := Str + ', ' + V.ToString;

      Memo1.Lines.Add(Str);
    end;
end;

end.