我正在制作一个双面文件scrbook，其中引用了其他章节、图表等。如果目标在同一页上，我想省略文本中的页码引用（即，如果我们在第 30 页，则不应该有写着“cfp 30”的文本）。对于标签 #1，可以使用以下命令实现此目的：
\newcounter{samepage}
\newcommand{\IfRefOnSamePage}[3]{%
\stepcounter{samepage}%
\label{cmd:samepage-\thesamepage}%
\ifthenelse{\equal{\getpagerefnumber{#1}}{\getpagerefnumber{cmd:samepage-\thesamepage}}}%
{#2}%
{#3}%
}
如果目标在同一页面上，则输出#2，否则输出#3。
现在，由于这本书是双面的，我希望读者如果目标在对页上，也不需要参考。我认为使用包xifthenand Ifthispageeven/-扩展条件以捕获这些情况应该是一项简单的任务odd：
\ifthenelse{%
\equal{\getpagerefnumber{#1}}{\getpagerefnumber{cmd:samepage-\thesamepage}}%
\OR
\Ifthispageodd{\equal{\getpagerefnumber{#1}}{\numexpr\getpagerefnumber{cmd:samepage-\thesamepage}-1}}{false}%
\OR
\Ifthispageeven{\equal{\getpagerefnumber{#1}}{\numexpr\getpagerefnumber{cmd:samepage-\thesamepage}+1}}{false}%
}%
{#2}%
{#3}%
这次尝试产生了许多错误，“未定义控制序列”、“缺少数字”、“参数有多余的 }”等等。我检查了三遍，但我的\ifthenelse语法有问题吗？还是我尝试进行 +/- 1 计算的方式有问题？
考虑一下这个MWE：
\documentclass{scrbook}
\usepackage{xifthen}
\usepackage{hyperref}
\newcounter{samepage}
\newcommand{\IfRefOnSamePage}[3]{%
\stepcounter{samepage}%
\label{cmd:samepage-\thesamepage}%
\ifthenelse{\equal{\getpagerefnumber{#1}}{\getpagerefnumber{cmd:samepage-\thesamepage}}}%
{#2}%
{#3}%
}
\newcommand{\IfRefOnDoublePage}[3]{%
\stepcounter{samepage}%
\label{cmd:samepage-\thesamepage}%
\ifthenelse{%
\equal{\getpagerefnumber{#1}}{\getpagerefnumber{cmd:samepage-\thesamepage}}%
\OR
\Ifthispageodd{\equal{\getpagerefnumber{#1}}{\numexpr\getpagerefnumber{cmd:samepage-\thesamepage}-1}}{false}%
\OR
\Ifthispageeven{\equal{\getpagerefnumber{#1}}{\numexpr\getpagerefnumber{cmd:samepage-\thesamepage}+1}}{false}%
}%
{#2}%
{#3}%
}
\begin{document}
\section{First page}
Text.
\newpage
\section{Second page}
% This works:
Read more about this\IfRefOnSamePage{target}{ on this page}{ on page \pageref{target}}.
% This throws errors, but also works:
Read more about this\IfRefOnDoublePage{target}{ here}{ on page \pageref{target}}.
\subsection{I am the reference target}
\label{target}
Text.
\newpage
\section{Third page}
% This works as expected, but it yields a reference I actually don't want:
Read more about this\IfRefOnSamePage{target}{ on this page}{ on page \pageref{target}}.
% This doesn't:
Read more about this\IfRefOnDoublePage{target}{ here}{ on page \pageref{target}}.
\end{document}