受益于此TeX.SE 答案我写了这段代码：
\documentclass[a5paper,openany,14pt,]{extbook}
\usepackage[left=2.34cm, right=2.34cm, top=2.66cm]{geometry}
\usepackage[explicit]{titlesec}
\titleformat{\chapter}[hang]
{\titlerule[2pt]\vspace{3pt}\titlerule\bfseries\Large\filleft}
{\Huge\thechapter}
{1ex}
{#1\filright \markboth{#1}{}} % add the leftmark <<<
\usepackage{fancyhdr}
\fancypagestyle{plain}{%
\fancyhf{}
\renewcommand{\headrulewidth}{0pt}
\fancyhead[RO]{\fontsize{14pt}{14pt}\selectfont\thepage}
\fancyhead[C]{\leftmark}
\fancyhead[LE]{\fontsize{14pt}{14pt}\selectfont\thepage}
}
\renewcommand{\chaptermark}[1]{\markboth{\chaptername\ \thechapter{}:
#1}{}}
\renewcommand{\sectionmark}[1]{\markright{\thesection{} #1}{}}
\pagestyle{plain}
\usepackage{soul} % package to stretch the chapter name horizontally
\begin{document}
\sodef\spaceout{}{0pt plus 1fil}{.4em plus 1fil}{0pt}
\chapter*{\makebox[\linewidth][l]{\spaceout{INTRODUCTION}}}% \chaptermark{Introduction}%
% If I add \chaptermark{Introduction then "Chapter 0: Introduction" appears which is not desired.
Alright, here we are...
\pagebreak
Alright, one more page...
\chapter*{\makebox[\linewidth][l]{\spaceout{HERE WE GO NOW}}}
Alright, here we are...
\pagebreak
Alright, one more page...
\end{document}
获取右侧屏幕截图中给出的布局类型：
怎么做？
答案1
您不应该在参数中使用标记：管理参数和标题中\chapter的排版。\titleformat
我不会重新定义plain样式，因为它用于章节开始页。
您缺少设置headheight。
而不是soul，我相信最好使用microtype。
最后，A5 纸上的字体大小是 14pt 吗？你确定吗？
\documentclass[a5paper,openany,14pt,]{extbook}
\usepackage[
left=2.34cm,
right=2.34cm,
top=2.66cm,
headheight=17pt,
]{geometry}
\usepackage{microtype}
\usepackage{fancyhdr}
\usepackage{titlesec}
\titleformat{\chapter}[hang]
{\titlerule[2pt]\vspace{3pt}\titlerule\bfseries\Large\filleft}
{\Huge\thechapter}
{1ex}
{\filright\spaceoutchaptertitle} % add the leftmark <<<
\newcommand{\spaceoutchaptertitle}[1]{\textls{\MakeUppercase{#1}}}
\fancypagestyle{thesis}{%
\fancyhf{}%
\renewcommand{\headrulewidth}{0pt}
\fancyhead[RO]{\fontsize{14pt}{14pt}\selectfont\thepage}%
\fancyhead[C]{\textls{\MakeUppercase{\leftmark}}}%
\fancyhead[LE]{\fontsize{14pt}{14pt}\selectfont\thepage}%
}
\renewcommand{\chaptermark}[1]{%
\markboth{\chaptername\ \thechapter{}: #1}{}%
}
\renewcommand{\sectionmark}[1]{\markright{\thesection\ #1}}
\pagestyle{thesis}
\begin{document}
\chapter*{Introduction}
\markboth{Introduction}{Introduction}
Alright, here we are...
\pagebreak
Alright, one more page...
\chapter{Here we go now}
Alright, here we are...
\pagebreak
Alright, one more page...
\end{document}
