将节点置于路径的中心

Question

为什么$\times 12$不在路径的中心？

\documentclass[border=3pt]{standalone}
\usepackage{tikz}

\begin{document}


\begin{tikzpicture}[bob/.style={outer sep=0pt,text width=2.5em,align=center,draw}]

\node[bob] (A) {1200} ;
\node[bob,anchor=east] (B) at (A.west) {100} ;

    \draw[>=stealth,->] (B.south)--++(0,-.3) -| (A.south)
        node[pos=.5,fill=white,inner sep=1pt] {\small$\times12$};


\end{tikzpicture}

\end{document}

Answer 1

如果您只想将节点置于路径的水平部分的中心，您可以将路径分成三段：

\documentclass[border=3pt]{standalone}
\usepackage{tikz}
\begin{document}

\begin{tikzpicture}[bob/.style={outer sep=0pt,text width=2.5em,align=center,draw}]

\node[bob] (A) {1200} ;
\node[bob,anchor=east] (B) at (A.west) {100} ;
  \draw[>=stealth,->] (B.south)--++(0,-.3)coordinate(h)
      --node[fill=white,inner sep=1pt] {\small$\times12$}(h-|A.south) 
      --(A.south);
\end{tikzpicture}

\end{document}