如何混合章节编号格式？（例如第 1 章、第 2 章、第 3 a 章、第 3 B 章、第 4 章）

Question

有没有一种简单的方法可以让 Latex 具有：

• 第1章
• 第2章
• 第 3 章
• 第 3b 章
• 第四章

之前提出类似问题的所有问题都很老了，而且似乎有一些复杂/不太可靠的方法来实现这一点。有没有一些简单而优雅的方法？

Answer 1

这似乎足够强大。如果您需要连续的子章节，请\resetchapters在您想要步进计数器时添加。

\documentclass[oneside]{book} % oneside is just to have smaller pictures

\usepackage[a6paper,margin=1cm,bottom=1.5cm,heightrounded]{geometry} % just to have smaller pictures

\usepackage{etoolbox} % needed for \preto

\newcounter{keepchapter}
\newif\ifsubchapter

\newcommand{\subchapter}{%
  \ifsubchapter
    % all is already set up
  \else
    \subchaptertrue
    \setcounter{keepchapter}{\value{chapter}}%
    \stepcounter{keepchapter}%
    \renewcommand{\thechapter}{\thekeepchapter\alph{chapter}}%
    \setcounter{chapter}{0}%
  \fi
  \standardchapter
}
\let\standardchapter\chapter
\preto\chapter{\resetchapter}
\newcommand{\resetchapter}{%
  \ifsubchapter
    \setcounter{chapter}{\value{keepchapter}}
    \subchapterfalse
    \renewcommand{\thechapter}{\arabic{chapter}}%
  \fi
}

\begin{document}

\frontmatter

\begingroup\scriptsize % just to have smaller pictures

\tableofcontents

\endgroup % just to have smaller pictures

\chapter{Introduction}

References

\ref{first} \ref{a}
\ref{second-a} \ref{b}
\ref{second-b} \ref{c}
\ref{third-a} \ref{d}
\ref{third-b} \ref{e}

\mainmatter

\chapter{First}\label{first}
\section{Test}\label{a}

\subchapter{Second A}\label{second-a}
\section{Test}\label{b}

\subchapter{Second B}\label{second-b}
\section{Test}\label{c}

\resetchapter
\subchapter{Third A}\label{third-a}
\section{Test}\label{d}

\subchapter{Third B}\label{third-b}
\section{Test}\label{e}

\chapter{Fourth}\label{fourth-b}
\section{Test}\label{f}

\subchapter{Fifth A}\label{fifth-a}
\section{Test}\label{g}

\subchapter{Fifth B}\label{fifth-b}
\section{Test}\label{h}

\end{document}

如果hyperref涉及，你需要添加几行

\newcounter{keepchapter}
\newif\ifsubchapter

\newcommand{\subchapter}{%
  \ifsubchapter
    % all is already set up
  \else
    \subchaptertrue
    \setcounter{keepchapter}{\value{chapter}}%
    \stepcounter{keepchapter}%
    \renewcommand{\thechapter}{\thekeepchapter\alph{chapter}}%
    \renewcommand{\theHchapter}{\thekeepchapter\alph{chapter}}%
    \setcounter{chapter}{0}%
  \fi
  \standardchapter
}
\let\standardchapter\chapter
\preto\chapter{\resetchapter}
\newcommand{\resetchapter}{%
  \ifsubchapter
    \setcounter{chapter}{\value{keepchapter}}
    \subchapterfalse
    \renewcommand{\thechapter}{\arabic{chapter}}%
    \renewcommand{\theHchapter}{\arabic{chapter}}%
  \fi
}