如何制定“钩子规则”

Question

我想这是一个非常基本的问题，但我什么也没找到。也不知道该搜索什么，抱歉标题太蠢了。

我怎样才能制作一个“带钩子的规则”，无论是水平的还是垂直的，具有一定的长度和厚度，例如

\rule{\linewidth}{1pt}

但就像下面的图片一样：

Answer 1

更新：

根据要求，为“挂钩”文本提供一个环境。语法如下：

\begin{hooked}[<optional line configuration (TikZ syntax)>]%
              {<Hook length (below horizontal rule)>}%
              {<The amount the hook advances to the margin>}%
              {<The space between the hook and the text>}
Text
\end{hooked}

我在钩子和文本之间添加了一个空格。留一点空间看起来会更好。

代码：

\newenvironment{hooked}[4][line width=1pt]{% Default line appearance
  \noindent\hspace{-#3}% Drag the hook left by \hookmargin
  \begin{tikzpicture}% Draw the opening hook
    %                                          V---V Why can't use 2#3 instead of #3+#3?
    \draw [#1] (0,-#2) -- (0,0) -- (\linewidth+#3+#3,0) -- (\linewidth+#3+#3,-#2);
  \end{tikzpicture}%
  \par% We need a \par to avoid text in the same line as the rules (thanks @Werner!)
  \vspace{#4}% Add a space between the hook and the text
  \def\closehook{% Defining a closing hook (for some reason, putting this in the \end{hooked} definition doesn't work)
    \par% And another \par here!
    \vspace{#4}% Add the same sspace as before
    \noindent\hspace{-#3}% Doing the same...
    \begin{tikzpicture}
      \draw [#1] (0, #2) -- (0,0) -- (\linewidth+#3+#3,0) -- (\linewidth+#3+#3, #2);
    \end{tikzpicture}%
  }%
}{%
  \closehook% Inserting the closing hook
}

梅威瑟：

\documentclass{article}
\usepackage{tikz}
\usepackage{lipsum}

\newenvironment{hooked}[4][line width=1pt]{%
  \noindent\hspace{-#3}%
  \begin{tikzpicture}
    \draw [#1] (0,-#2) -- (0,0) -- (\linewidth+#3+#3,0) -- (\linewidth+#3+#3,-#2);
  \end{tikzpicture}\par\vspace{#4}%
  \def\closehook{%
    \par\vspace{#4}\noindent\hspace{-#3}%
    \begin{tikzpicture}
      \draw [#1] (0, #2) -- (0,0) -- (\linewidth+#3+#3,0) -- (\linewidth+#3+#3, #2);
    \end{tikzpicture}%
  }}{\closehook}

\begin{document}

\begin{hooked}[line width=1pt, blue, dash dot]{2em}{2em}{-1em}

\lipsum[1-5]

\end{hooked}

\end{document}

我之前的回答：

使用 TikZ：

\documentclass{article}
\usepackage{tikz}
\usepackage{lipsum}

\newlength{\hooklength}
\setlength{\hooklength}{1em}% The length of the hook below the horizontal rule

\newlength{\hookmargin}
\setlength{\hookmargin}{2em}% The amount the hook enters the margin to each side

\newlength{\hookwidth}
\setlength{\hookwidth}{1pt}% The thickness of the rules

\newcommand{\hookdown}{%
\noindent\hspace{-\hookmargin}%
\begin{tikzpicture}
  \draw [line width = \hookwidth] (0,-\hooklength) -- (0,0) -- (\textwidth+2\hookmargin,0) -- (\textwidth+2\hookmargin,-\hooklength);
\end{tikzpicture}%
}

\newcommand{\hookup}{%
\noindent\hspace{-\hookmargin}%
\begin{tikzpicture}
  \draw [line width = \hookwidth] (0,\hooklength) -- (0,0) -- (\textwidth+2\hookmargin,0) -- (\textwidth+2\hookmargin,\hooklength);
\end{tikzpicture}%
}

\begin{document}
\hookdown

\lipsum[1]

\hookup
\end{document}

Answer 2

一个简单的解决方案是使用 quoting和mathtools：

\documentclass{article}
\usepackage{mathtools}
\usepackage{quoting}
\usepackage{lipsum}

\begin{document}

\lipsum[1]
\begin{quoting}[leftmargin = 0.75em, rightmargin = 0.75em, indentfirst = false,%
 begintext = \noindent{\centering\hspace{-0.75em}$\overbracket[1pt][1ex]{\hspace*{\textwidth}}$}\vspace{-1.1ex}\par\nopagebreak\noindent, %
 endtext = \vspace{-2.25ex}\nopagebreak\noindent\centering{\hspace{-0.75em}$\underbracket[1pt][1ex]{\hspace*{\textwidth}}$}]
  \lipsum[1]
\end{quoting}
\lipsum[2]

\end{document}