在命令前设置环境的布尔值

Question 1

这个怎么样？

\documentclass[12pt]{article}
\usepackage{etoolbox}
\newbool{blbt}
\newbool{blvd}
\newcommand{\classify}{The environment below is 
    \ifbool{blvd}{Example}{\ifbool{blbt}{Problem}{Wrong}}}
%%%=======================
\newenvironment{bt}{\global\setbool{blvd}{false}\global\setbool{blbt}{true}{\bfseries\classify}\par}{}
%%%=======================
\newenvironment{vd}{\global\setbool{blvd}{true}\global\setbool{blbt}{false}{\bfseries\classify}\par}{}
%%%=======================
\begin{document}
    \begin{bt}
     Contents PPP
    \end{bt}
    
    \begin{vd}
     Contents EXEXEX
    \end{vd}
\end{document}

Answer

这个怎么样？

\documentclass[12pt]{article}
\usepackage{etoolbox}
\newbool{blbt}
\newbool{blvd}
\newcommand{\classify}{The environment below is 
    \ifbool{blvd}{Example}{\ifbool{blbt}{Problem}{Wrong}}}
%%%=======================
\newenvironment{bt}{\global\setbool{blvd}{false}\global\setbool{blbt}{true}{\bfseries\classify}\par}{}
%%%=======================
\newenvironment{vd}{\global\setbool{blvd}{true}\global\setbool{blbt}{false}{\bfseries\classify}\par}{}
%%%=======================
\begin{document}
    \begin{bt}
     Contents PPP
    \end{bt}
    
    \begin{vd}
     Contents EXEXEX
    \end{vd}
\end{document}

Question 2

如果你不介意你的命令\classify和环境bt并且vt有一个非可选的参数，那么你可以使用该包参考值并且有

环境 bt和vt位置引用标签的属性blvd和blbt
该命令\classify从这些引用标签中提取属性的值：

\documentclass[12pt]{article}
\usepackage{etoolbox}
\usepackage{zref}

\makeatletter
\@ifdefinable\@zrefpropdefined{%
  \ZREF@Robust\def\@zrefpropdefined{%
    \zref@wrapper@babel\@ZREFpropdefined
  }%
}%
\@ifdefinable\@ZREFpropdefined{%
  \def\@ZREFpropdefined#1#2#3#4{%
    % #1  - label
    % #2  - property
    % #3  - tokens in case label and property are available
    % #4  - tokens in case label undefined or property not available
    \zref@ifrefundefined{#1}{%
       \zref@refused{#1}#4%
    }{%
      \zref@ifrefcontainsprop{#1}{#2}{#3}{%
        \protect\G@refundefinedtrue
        \@latex@warning{%
           Missing property `#2' in reference `#1' on page \thepage
        }%
        #4%
      }%
    }%
  }%
}%
\zref@newprop{blbt}{false}%
\zref@newprop{blvd}{false}%
\newcommand\blvdANDblbtLABEL[3]{%
  \zref@setcurrent{blvd}{#1}%
  \zref@setcurrent{blbt}{#2}%
  \zref@wrapper@immediate{%
    \zref@labelbyprops{#3}{blbt,blvd}%
  }%
}%
%%%=======================
\newenvironment{bt}[1]{%
  \blvdANDblbtLABEL{false}{true}{#1}%
  % Here you could place code that forks 
  % via \ifbool{\zref@getcurrent{blvd}}{<true>}{<false>}%
  % and \ifbool{\zref@getcurrent{blbt}}{<true>}{<false>}%
\par}{}
%%%=======================
\newenvironment{vd}[1]{%
  \blvdANDblbtLABEL{true}{false}{#1}%
  % Here you could place code that forks 
  % via \ifbool{\zref@getcurrent{blvd}}{<true>}{<false>}%
  % and \ifbool{\zref@getcurrent{blbt}}{<true>}{<false>}%
\par}{}
%%%=======================
\newcommand{\classify}[1]{The below environment is 
  \@zrefpropdefined{#1}{blvd}{%
    \@zrefpropdefined{#1}{blbt}{\@firstoftwo}{\@secondoftwo}%
  }{%
    \@zrefpropdefined{#1}{blbt}{}{}%
    \@secondoftwo
  }%
  {%
    \ifbool{\zref@extractdefault{#1}{blvd}{}}{Example}{%
      \ifbool{\zref@extractdefault{#1}{blbt}{}}{Problem}{Wrong}%
    }%
  }{%
    \nfss@text{\reset@font\bfseries??}%
  }%
}%
\makeatother

\begin{document}

{\bfseries\classify{Label Of This Environment}}
    \begin{bt}{Label Of This Environment}
     Contents PPP
    \end{bt}
    
{\bfseries\classify{Label Of That Environment}}
    \begin{vd}{Label Of That Environment}
     Contents EXEXEX
    \end{vd}

\end{document}

（如果现实生活场景也只涉及两个环境，则可以使用单个布尔值来执行“如果\classify可以省略-command 的错误大小写”。）

使用参考值 你可能根本不需要布尔值：

\documentclass[12pt]{article}
\usepackage{zref}

\makeatletter

\@ifdefinable\@zrefpropdefined{%
  \ZREF@Robust\def\@zrefpropdefined{%
    \zref@wrapper@babel\@ZREFpropdefined
  }%
}%
\@ifdefinable\@ZREFpropdefined{%
  \def\@ZREFpropdefined#1#2#3#4{%
    % #1  - label
    % #2  - property
    % #3  - tokens in case label and property are available
    % #4  - tokens in case label undefined or property not available
    \zref@ifrefundefined{#1}{%
       \zref@refused{#1}#4%
    }{%
      \zref@ifrefcontainsprop{#1}{#2}{#3}{%
        \protect\G@refundefinedtrue
        \@latex@warning{%
           Missing property `#2' in reference `#1' on page \thepage
        }%
        #4%
      }%
    }%
  }%
}%

\zref@newprop{environmentphrase}{unknown}%
\newcommand\environmentphraseLABEL[2]{%
  \zref@setcurrent{environmentphrase}{#1}%
  \zref@wrapper@immediate{%
    \zref@labelbyprops{#2}{environmentphrase}%
  }%
}%
%%%=======================
\newenvironment{bt}[1]{%
  \environmentphraseLABEL{Problem}{#1}%
\par}{}
%%%=======================
\newenvironment{vd}[1]{%
  \environmentphraseLABEL{Example}{#1}%
\par}{}
%%%=======================
\newcommand{\classify}[1]{The below environment is 
  \zref@extractdefault{#1}{environmentphrase}{%
    \@zrefpropdefined{#1}{environmentphrase}{%
      \protect\G@refundefinedtrue
      \@latex@warning{%
        Unspecified problem in reference `#1' on page \thepage
      }%
    }{}%
    \nfss@text{\reset@font\bfseries??}%
  }%
}%
\makeatother

\begin{document}

{\bfseries\classify{Label Of This Environment}}
    \begin{bt}{Label Of This Environment}
     Contents PPP
    \end{bt}
    
{\bfseries\classify{Label Of That Environment}}
    \begin{vd}{Label Of That Environment}
     Contents EXEXEX
    \end{vd}

\end{document}

对于这两个示例，您需要两个 LaTeX 编译（在两次运行之间无需删除辅助文件）以使所有内容匹配。

这两个示例生成的 .pdf 文件如下所示：

Answer