tikzcd 環境：雙/平行箭頭錯誤？

Question

\documentclass{beamer}

\usepackage{tikz-cd}
\usetikzlibrary{matrix}

\begin{document}
\begin{frame}[fragile]

\begin{center}
\begin{tikzcd}[row sep=2.3cm, column sep = 
2.3cm]
A\arrow{r}{e}\arrow{d}[swap]{f} & B\arrow{r} 
{e1} \arrow{d}{g} &B1 \arrow{d}{g1}\\
C\arrow{r}[swap]{h} & D \arrow{r}[swap] 
{h}&D1\\
\end{tikzcd}
\end{center}

\end{frame}


\end{document}

在這裡我想將每個箭頭更改為雙/平行箭頭。我正在使用Leftrightarrow選項，例如 ，\arrow{r, Leftrightarrow}但出現錯誤。

任何解決問題的幫助將不勝感激。

Answer 1

您可以使用該選項arrows=Leftrightarrow

\documentclass{beamer}

\usepackage{tikz-cd}
\usetikzlibrary{matrix}

\begin{document}
\begin{frame}[fragile]

\begin{center}
\begin{tikzcd}[
  row sep=2.3cm,
  column sep=2.3cm,
  arrows=Leftrightarrow,
]
A\arrow{r}{e}\arrow{d}[swap]{f} & B\arrow{r}
{e1} \arrow{d}{g} &B1 \arrow{d}{g1}\\
C\arrow{r}[swap]{h} & D \arrow{r}[swap]
{h}&D1\\
\end{tikzcd}
\end{center}

\end{frame}

\end{document}

「現代」語法更簡單：

\begin{tikzcd}[
  row sep=2.3cm,
  column sep=2.3cm,
  arrows=Leftrightarrow,
]
A \arrow[r,"e"] \arrow[d,swap,"f"] &
B \arrow[r,"e1"] \arrow[d,"g"] &
B1 \arrow[d,"g1"]
\\
C \arrow[r,swap,"h"] & D \arrow[r,swap,"h"] &
D1
\end{tikzcd}

假設只有左上角的箭頭應該是Leftrightarrow；那麼它可以輸入為

\arrow[r,Leftrightarrow,"e"]

例如，與

\begin{tikzcd}[
  row sep=2.3cm,
  column sep=2.3cm,
]
A \arrow[r,Leftrightarrow,"e"] \arrow[d,swap,"f"] &
B \arrow[r,"e1"] \arrow[d,"g"] &
B1 \arrow[d,"g1"]
\\
C \arrow[r,swap,"h"] & D \arrow[r,swap,"h"] &
D1
\end{tikzcd}

你會得到