编辑

Question

基于答案http://tex.stackexchange.com/a/304044/103076通过 wrtlprnft，我有以下代码

   \documentclass[tikz,margin=1cm]{standalone}
   \usetikzlibrary{decorations.markings}
   \begin{document}
   \begin{tikzpicture}
        \tikzstyle{arrowed double line}=[
            dashed, double distance between line centers=3pt,
            postaction=decorate,
            decoration={
                markings,
                mark=between positions 10pt and -10pt step 20pt with {
                    \arrow[thin,yshift= 1.5pt,xshift=.8pt]{>}
                    \arrow[thin,yshift=-1.5pt,xshift=.8pt]{<}
                },
            },
        ]
        \draw[arrowed double line] (0,0) --  (1,2);
    \end{tikzpicture}
\end{document}

结果是：

我对虚线之间的模糊横线感到不满。我甚至不知道 tikz 为什么决定画出它们。

有办法除掉它们吗？

提前感谢所有回复。

PS 同样的事情也发生在双实线的端点

Answer 1

你可以尝试这个：

\documentclass[border=10pt,multi,tikz]{standalone}
\usetikzlibrary{decorations.markings}
\begin{document}
\begin{tikzpicture}
  [arrowed double line/.style={% \tikzstyle is deprecated
  preaction={
    draw=black,
    dashed,
    double distance between line centers=3pt,
    line width=.4pt,
  },
  draw=white,
  line width=3pt,
  postaction={
    decorate,
  },
  decoration={
    markings,
    mark=between positions 10pt and -10pt step 20pt with {
      \arrow [thin,black,yshift= 1.5pt,xshift=.8pt]{>}
      \arrow [thin,black,yshift=-1.5pt,xshift=.8pt]{<}
    },
  },
  }]
  \path[arrowed double line] (0,0) --  (1,2);
\end{tikzpicture}
\end{document}

编辑

如果要去除线条末端的痕迹，可以使用shorten负尺寸来表示白线。显然，这需要小心一点，以免覆盖图片中已有的任何内容。

例如，

\begin{tikzpicture}
  [arrowed double line/.style={% \tikzstyle is deprecated
    preaction={
      draw=black,
      dashed,
      double distance between line centers=3pt,
      line width=.4pt,
      shorten >=0pt,
      shorten <=0pt,
    },
    draw=white,
    line width=3pt,
    shorten >=-.1pt,
    shorten <=-.1pt,
    postaction={
      decorate,
    },
    decoration={
      markings,
      mark=between positions 10pt and -10pt step 20pt with {
        \arrow [thin,black,yshift= 1.5pt,xshift=.8pt]{>}
        \arrow [thin,black,yshift=-1.5pt,xshift=.8pt]{<}
      },
    },
  }]
  \path[arrowed double line] (0,0) --  (1,2);
\end{tikzpicture}

产生以下行结尾：