垂直对齐表格的第一行多行

Question

我正在为一个两列文档使用 IEEEtran 样式。我希望我的表格单元格水平和垂直居中对齐。第一行必须是多行，并且某些列的行数多于其他列，但我的代码没有将其水平居中对齐。

\begin{tabular}{|c|c|c|c|}
\hline
\multicolumn{1}{|p{0.2\columnwidth}|}{\centering {\bfseries a few rows of text}} & \multicolumn{1}{p{0.2\columnwidth}|}{\centering {\bfseries a few rows of text}} & \multicolumn{1}{p{0.2\columnwidth}|}{\centering {\bfseries a few rows of text}} & \multicolumn{1}{p{0.2\columnwidth}|}{\centering {\bfseries a few more more rows of text}}\\
\hline
Three & Four&5&6\\
\hline
\end{tabular}

由此产生了如下结果：

显然第一行没有垂直对齐在中心。

有没有什么简单的办法可以解决这个问题？

Answer 1

有多种方法可以实现这一点。要么使用array的m{<len>}列（而不是p{<len>}），它会自动将锚点置于垂直中心。或者，使用makecell手动堆叠内容（这也提供了默认的垂直中心对齐：

\documentclass{IEEEtran}

\usepackage{makecell,array}

\begin{document}

\begin{tabular}{|c|c|c|c|}
  \hline
  \multicolumn{1}{|p{0.2\columnwidth}|}{\centering\bfseries a few rows of text} 
    & \multicolumn{1}{p{0.2\columnwidth}|}{\centering\bfseries a few rows of text}
    & \multicolumn{1}{p{0.2\columnwidth}|}{\centering\bfseries a few rows of text}
    & \multicolumn{1}{p{0.2\columnwidth}|}{\centering\bfseries a few more more rows of text} \\
  \hline
  Three & Four& 5 & 6 \\
  \hline
\end{tabular}

\bigskip

\begin{tabular}{|c|c|c|c|}
  \hline
  \multicolumn{1}{|m{0.2\columnwidth}|}{\centering\bfseries a few rows of text} 
    & \multicolumn{1}{m{0.2\columnwidth}|}{\centering\bfseries a few rows of text}
    & \multicolumn{1}{m{0.2\columnwidth}|}{\centering\bfseries a few rows of text}
    & \multicolumn{1}{m{0.2\columnwidth}|}{\centering\bfseries a few more more rows of text} \\
  \hline
  Three & Four& 5 & 6 \\
  \hline
\end{tabular}

\bigskip

\begin{tabular}{|c|c|c|c|}
  \hline
  \multicolumn{1}{|p{0.2\columnwidth}|}{\bfseries \makecell{a few rows \\ of text}}
    & \multicolumn{1}{p{0.2\columnwidth}|}{\bfseries \makecell{a few rows \\ of text}}
    & \multicolumn{1}{p{0.2\columnwidth}|}{\bfseries \makecell{a few rows \\ of text}}
    & \multicolumn{1}{p{0.2\columnwidth}|}{\bfseries \makecell{a few more \\ more rows \\ of text}} \\
  \hline
  Three & Four& 5 & 6 \\
  \hline
\end{tabular}

\end{document}

Answer 2

我不明白为什么您要将列标题放入列类型multicolum中p，然后再水平居中内容。您喜欢确定表格宽度吗？如果不是，那么看看以下解决方案是否能满足您的要求：

\documentclass{IEEEtran}
\usepackage{makecell}
\renewcommand\theadfont{\normalsize\bfseries}% <-- defined fonts for column heads

\usepackage{lipsum}% for dummy text

\begin{document}
\lipsum[2]
    \begin{table}[htb]
    \centering
\caption{my table}
    \label{tab:very-important-table}
\setlength\extrarowheight{2pt}
\begin{tabular}{|c|c|c|c|}
  \hline
\thead{a few rows\\ of text}
        &   \thead{a few rows\\ of text}
                    &   \thead{a few rows\\ of text}
                            &   \thead{a few more\\ more rows\\ of text} \\
  \hline
Three   &   Four    &   5   &   6   \\
  \hline
\end{tabular}
    \end{table}
\lipsum
\end{document}

如果是，那么这个包tabularx可以帮助：

\documentclass{IEEEtran}
\usepackage{makecell,tabularx} % <-- added tabularx
\renewcommand\theadfont{\normalsize\bfseries}
\newcolumntype {C}{>{\centering\arraybackslash}X}% <-- defined new column type
\usepackage{lipsum}% for dummy text

\begin{document}
\lipsum[2]
    \begin{table}[htb]
    \setlength\extrarowheight{2pt}
    \centering
\caption{my table}
    \label{tab:very-important-table}
\begin{tabularx}{\columnwidth}{|C|C|C|C|}% determined table width 
  \hline
\thead{a few rows\\ of text}
        &   \thead{a few rows\\ of text}
                    &   \thead{a few rows\\ of text}
                            &   \thead{a few more\\ more rows\\ of text} \\
  \hline
Three   &   Four    &   5   &   6   \\
  \hline
\end{tabularx}
    \end{table}
\lipsum
\end{document}