CombineStringArrays

procedure CombineStringArrays(var Arr: TStringArray; ArrToAdd: TStringArray);
var
  I, L1, L2: Integer;
begin
  L1 := Length(Arr);
  SetLength(Arr, L1 + Length(ArrToAdd));
  L2 := Length(Arr);
  for I := L1 to (L2 - 1) do
    Arr[I] := ArrToAdd[I - L1];
end;