將 tabularx 單元格居中時錯位 \noalign

Question

我有一個最小的 LaTeX 文檔，如下所示：

\documentclass{article}
\usepackage{tabularx}
\begin{document}
  \noindent
  \begin{tabularx}{\linewidth}{ X | X }
    \centering A & B \\ \hline
    1.0 & 2.0 \\
  \end{tabularx}
\end{document}

我想將表標題居中，但將列左對齊。但是，當我添加\centering到 B 標頭時，如下所示：

\documentclass{article}
\usepackage{tabularx}
\begin{document}
  \noindent
  \begin{tabularx}{\linewidth}{ X | X }
    \centering A & \centering B \\ \hline
    1.0 & 2.0 \\
  \end{tabularx}
\end{document}

我收到此錯誤：

! Misplaced \noalign.
\hline ->\noalign
                  {\ifnum 0=`}\fi \hrule \@height \arrayrulewidth \futurelet...
l.8   \end{tabularx}

! Extra alignment tab has been changed to \cr.
<recently read> \endtemplate

l.8   \end{tabularx}

! Misplaced \noalign.
\hline ->\noalign
                  {\ifnum 0=`}\fi \hrule \@height \arrayrulewidth \futurelet...
l.8   \end{tabularx}

! Extra alignment tab has been changed to \cr.
<recently read> \endtemplate

l.8   \end{tabularx}

! Misplaced \noalign.
\hline ->\noalign
                  {\ifnum 0=`}\fi \hrule \@height \arrayrulewidth \futurelet...
l.8   \end{tabularx}

! Extra alignment tab has been changed to \cr.
<recently read> \endtemplate

l.8   \end{tabularx}

Answer 1

文件的第 2 頁tabularx說您必須在(或或)\arraybackslash之後使用。像這樣使用：\centering\raggedright\ragggedleft

\documentclass{article}
\usepackage{tabularx}
\begin{document}
  \noindent
  \begin{tabularx}{\linewidth}{ X | X }
    \centering\arraybackslash A & \centering\arraybackslash B \\ \hline
    1.0 & 2.0 \\
  \end{tabularx}
\end{document}

LaTeX 的文字對齊命令重新定義，\\因此它們不再意味著「表格中的新行」。該\arraybackslash命令執行\let\\\tabularnewline後它將再次工作。

或者，您可以在第一行末尾使用\tabularnewline代替。\\

\documentclass{article}
\usepackage{tabularx}
\begin{document}
  \noindent
  \begin{tabularx}{\linewidth}{ X | X }
    \centering A & \centering B \tabularnewline \hline
    1.0 & 2.0 \\
  \end{tabularx}
\end{document}

Answer 2

您可以簡單地使用 a\multicolumn{1}{c}{...}作為列標題。或者載入makecell並使用它的thead命令（預設情況下，它的內容水平和垂直居中），它可以定義所有theads 參數的通用格式。以下是這兩種方法的範例：

\documentclass{article}
\usepackage{tabularx, makecell, xcolor}
\renewcommand{\theadfont}{\normalsize\bfseries\color{red}}

\begin{document}

  \noindent
  \begin{tabularx}{\linewidth}{ X | X }
    \multicolumn{1}{c}{A} & \multicolumn{1}{c}{B} \\ \hline
    1.0 & 2.0 \\
  \end{tabularx}
\vspace{4ex}

  \noindent
  \begin{tabularx}{\linewidth}{ X | X }
    \thead{A} & \thead{B} \\ \hline
    1.0 & 2.0 \\
  \end{tabularx}

\end{document}