[AND_REY]

Код:

const
 x = 'xxxxx';
var
 y, s: String;
begin
 y:= 'динамика';
 s:= x + y;
 //далее ищем окно с названием s; 
end;

Может так ещё:

Код:

Function FindWnd(S: String): HWND;
Var
 Wnd: HWnd;
 buff: Array [0..127] of Char;
begin
 FindWnd:= 0;
 Wnd:= GetWindow(Form1.Handle,gw_HWndFirst);
 While Wnd <> 0 Do
  begin
   if (Wnd <> Application.Handle ) And
      IsWindowVisible(Wnd) And
      (GetWindow(Wnd,gw_Owner) = 0) And
      (GetWindowText(Wnd, buff, SizeOf(buff)) <> 0) Then
       begin
        GetWindowText(Wnd, buff, SizeOf(buff));
        if Pos(S, StrPas(buff)) > 0 Then
         begin
          FindWnd:= Wnd;
          Break;
         end;
        end;
   Wnd:= GetWindow(Wnd, gw_hWndNext);
  end;
end;