%%
%% The LaTeX Companion, 3ed
%%
%% Example 6-6-3 on page I-469 in "\protect \nxLPack {arydshln} --- Dashed rules".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{111.0pt}
%StartShownPreambleCommands
\usepackage{array,arydshln}
  \setlength\extrarowheight{4pt}% extra space on row top
%StopShownPreambleCommands

\begin{document}
\begin{tabular}{|c::c|c|}    \hline
   A    & B  & C          \\ \hdashline\hline
   a    & b  & c          \\ \hdashline\hdashline
  1000  & 10 & 1          \\ \hdashline
   X    & Y  & Z          \\ \hline
\end{tabular}
\end{document}