日期翻译成中文

Question

英文日期是字符串，如1 January 2016。为了将它们翻译成中文，我使用以下方法，借助日期计算。

\usepackage{advdate,xparse}
\ExplSyntaxOn
\DeclareExpandableDocumentCommand{\StrMonthToNum}{ m }
{
  \str_case:nnF { #1 } {
    { January   } {  1 }
    { February  } {  2 }
    { March     } {  3 }
    { April     } {  4 }
    { May       } {  5 }
    { June      } {  6 }
    { July      } {  7 }
    { August    } {  8 }
    { September } {  9 }
    { October   } { 10 }
    { November  } { 11 }
    { December  } { 12 }
  } { 12 } % Wrong month, defaults to December/12
}
\ExplSyntaxOff

\begin{document}
\begin{CJK}{UTF8}{gbsn}
\def\cndate #1 #2 #3 {%
  #3年% Set year
  \StrMonthToNum{#2}月% Set month
  #1日% Set day
}

\cndate 1 January 2016 

\end{CJK}
\end{document}

输出结果如下：

但是，日期存储在命令中，例如\newcommand{\ENGLISHDATE}{1 January 2016}。如果要像这样执行，有什么方法可以获取它吗：\cndate{\ENGLISHDATE{}}？

Answer 1

我手头没有CJK——我用其他符号替换了环境和中文符号。

该\cndate宏明确要求 3 个参数，以空格分隔。这不是由\mydate或等简单宏提供的\ENGLISHDATE。

我建议重命名\cndate为\cndateinternal并定义\cndate为

\def\cndate#1{%
 \expandafter\cndateinternal#1%
}

这将首先扩展参数 #1，并因此“准备”输入\cndateinternal。

\documentclass{article}
\usepackage{advdate,xparse}
\ExplSyntaxOn
\DeclareExpandableDocumentCommand{\StrMonthToNum}{+m }
{
  \str_case:nnF { #1 } {
    { January   } {  1 }
    { February  } {  2 }
    { March     } {  3 }
    { April     } {  4 }
    { May       } {  5 }
    { June      } {  6 }
    { July      } {  7 }
    { August    } {  8 }
    { September } {  9 }
    { October   } { 10 }
    { November  } { 11 }
    { December  } { 12 }
  } { 12 } % Wrong month, defaults to December/12
}
\ExplSyntaxOff

\newcommand{\mydate}{29 February 2016}

\begin{document}

\def\cndate#1{%
  \expandafter\cndateinternal#1%
}



\def\cndateinternal#1 #2 #3 {%
  #3$\dagger$% Set year
  \StrMonthToNum{#2}$\sum$% Set month
  #1$\pi$% Set day
}


\cndateinternal 1 January 2016 %
\cndate 5 March 2017 %
\cndate{\mydate}  % Braces needed

\end{document}

更新

这是一个带有包装器的版本，它负责处理最终的外括号等。

\documentclass{article}
\usepackage{advdate}
\usepackage{xparse}
\usepackage{l3regex}
\ExplSyntaxOn
\DeclareExpandableDocumentCommand{\StrMonthToNum}{+m }
{
  \str_case_x:nnF { #1 } {
    { January   } {  1 }
    { February  } {  2 }
    { March     } {  3 }
    { April     } {  4 }
    { May       } {  5 }
    { June      } {  6 }
    { July      } {  7 }
    { August    } {  8 }
    { September } {  9 }
    { October   } { 10 }
    { November  } { 11 }
    { December  } { 12 }
  } { 12 } % Wrong month, defaults to December/12
}

\NewDocumentCommand{\CnDate}{+m}{%
  \tl_set:Nx \l_tmpa_tl {#1} % Expand the date string to a token list
  \tl_trim_spaces:N \l_tmpa_tl % Remove spaces tail and head
  \regex_replace_all:nnN {\s} {;} \l_tmpa_tl  % Replace space '\s` with `;`
  \seq_set_split:NnV \l_tmpa_seq {;} {\l_tmpa_tl} % Split the sequence
  \DisplayCnDate{\seq_item:Nn \l_tmpa_seq {1}}{\seq_item:Nn \l_tmpa_seq {2}}{\seq_item:Nn \l_tmpa_seq {3}} % Display the date
}
\ExplSyntaxOff


\NewDocumentCommand{\DisplayCnDate}{mmm}{%
  #3$\dagger$% Set year
  \StrMonthToNum{#2}$\sum$% Set month
  #1$\pi$% Set day
}







\newcommand{\mydate}{29 February 2016}

\begin{document}

\CnDate{\mydate} %works

\CnDate \mydate %works

\CnDate 15 January 2016 % Does not work 
\DisplayCnDate 15 January 2016 % Does not work too 

\CnDate{ 15 January 2016                  } % works

(\CnDate{ 15 January 2016                  }) % works


\end{document}