将文本置于单个表格单元格的中心

Question

假设我有一个简单的表格。虽然我希望列总体上左右对齐，但我希望某些单元格居中。

\documentclass[12pt,a4paper]{book}

\def\x{This is a paragraph of text that should be flush both right and left. Centering an adjacent cell should not cause this cell to be centered.}
\def\y{Centered text}

\begin{document}
\centering
\begin{tabular}{p{2in}|p{2in}}
\x & \y \\
\y & \x \\
\x & \x
\end{tabular}

\end{document}

这具有我所期望的输出。

但是，当我想将标有“居中文本”的单元格居中时，我该怎么做？我尝试使用以下命令执行此\centering操作，

\def\y{\centering Centered text}

但出现以下错误：

! Extra alignment tab has been changed to \cr.

我怎样才能使个别单元格居中？

Answer 1

发生错误是因为\\被 重新定义\centering（以及其他命令，例如\raggedright），但问题只发生在最后一列。要修复它，您可以加载包array并在单元格中添加\arraybackslash，\centering这将恢复 的定义\\。

Gonzalo Medina 在评论中提到的另一个选择是使用\tabularnewline而不是\\来结束行，这并不需要array：

\x & \centering\y \tabularnewline

（该\arraybackslash命令简单定义为\def\arraybackslash{\let\\\tabularnewline}）

完整示例：

\documentclass[12pt,a4paper]{book}
\usepackage{array}

\def\x{This is a paragraph of text that should be flush both right and left. Centering an adjacent cell should not cause this cell to be centered.}
\def\y{Centered text}

\begin{document}
\centering
\begin{tabular}{p{2in}|p{2in}}
\x & \centering\arraybackslash\y \\
% \x & \centering\y \tabularnewline  % alternative version of the previous line
\centering\y & \x \\
\x & \x
\end{tabular}

\end{document}

Answer 2

添加跨越单列的多列。

\documentclass[12pt,a4paper]{book}

\def\x{This is a text aligned according to column alignment defined in tablular.}
\def\y{Centered text}
  
\begin{document}

\begin{tabular}{l|l}
   \x & \x \\
   \x & \x \\
   \multicolumn{1}{c}{\y} & \x 
\end{tabular}
 
\endtabular}

\end{document}