使用 \tcbsetmacrotoheightofnode 和 tcolorbox 中的维度

Question

\tcbsetmacrotoheightofnode需要节点的名称，而不是节点本身的整个定义。例如，如果您执行 \node (A) at (1,1) {Foobar};或\node [name=A] at (1,1) {Foobar};，则A是节点的名称，并且

\tcbsetmacrotoheightofnode\myheight{A}

将给出节点的高度。

因此你需要修改你的\myboxnode宏，例如

\newcommand{\myboxnode}[2]{%
\node[fill=#2!5!white, draw=#2!75!black, line width=.5pt, 
    below right, minimum height=2em, 
   text width=.8cm, align=center,
   font=\bfseries] (tmpbox) at ([xshift=3mm,yshift=-1mm]frame.north east) {#1 \thetcbcounter}}

注意添加(tmpbox)。然后您可以添加

\tcbsetmacrotoheightofnode\myheight{tmpbox}

之后立即上线\myboxnode{#2}{#1}，稍后使用\myheight。

完整代码（请注意，\dimexpr您不再需要）：

\documentclass{book}

\usepackage[most]{tcolorbox}
\usepackage{varwidth}
\tcbuselibrary{skins,breakable}

%\usepackage{polyglossia}
%\setmainlanguage{english}

\newcommand{\myboxnode}[2]{%
\node[fill=#2!5!white, draw=#2!75!black, line width=.5pt, 
    below right, minimum height=2em, 
   text width=.8cm, align=center,
   font=\bfseries] (tmpbox) at ([xshift=3mm,yshift=-1mm]frame.north east) {#1 \thetcbcounter}}

\tcbset{
    mystyle/.style 2 args={
        enhanced jigsaw, breakable, 
        colback=white, colframe=white, 
        sharp corners, 
        boxrule = 0mm, 
        top=2mm, bottom=2mm, left=2mm, right=2mm,
%       varwidth boxed title,
        tikznode boxed title={minimum width=\textwidth/4-15mm-4.5mm},
        attach boxed title to top right={%
            xshift=.5mm,yshift=- \tcboxedtitleheight+.5mm},
        boxed title style={%
            enhanced,
            sharp corners, 
            colframe=#1!75!black, 
            left=1mm, right=1mm,
            boxrule=.5mm},
        colbacktitle=#1!5!white, 
        coltitle=black,
        extrude right by=-15mm,
        underlay unbroken and first={%
            \myboxnode{#2}{#1};
            \tcbsetmacrotoheightofnode\myheight{tmpbox}
            \draw [#1!75!black,line width=.5mm]
              ([shift={(15mm-.5\pgflinewidth, -\myheight+.5\pgflinewidth)}]frame.north east) |- 
              ([shift={(-\textwidth/4+15mm,+.5\pgflinewidth)}]frame.north east);
            \draw [#1!75!black,line width=.5mm]
              ([shift={(.5\pgflinewidth,-\myheight+.5\pgflinewidth)}]frame.north west) |-
              ([shift={(\textwidth/4,+.5\pgflinewidth)}]frame.north west);

           \draw [#1!75!black,line width=.5mm] ([yshift=.25mm]frame.south west)(\textwidth/4,0) -- (0,0);
           \draw [#1!75!black,line width=.5mm] ([xshift=.25mm,yshift=.25mm]frame.south west) -- +(0,\myheight);
           \draw [#1!75!black,line width=.5mm] ([xshift=14.75mm,yshift=.25mm]frame.south east) -- +(0,\myheight);
           \draw [#1!75!black,line width=.5mm] ([yshift=.25mm]frame.south east)(3*\textwidth/4,0) -- (\textwidth,0);
         },
    },
    mytitle/.style 2 args={
        code={%
            \ifstrempty{#1}
            {\tcbset{
                before upper={\parshape 4
                    0pt \dimexpr \hsize-14mm\relax
                    0pt \dimexpr \hsize-14mm\relax
                    0pt \dimexpr \hsize-14mm\relax
                    0pt \hsize}}}
            {\tcbset{
                title={#1},
                before upper={\vspace*{\baselineskip}\parshape 3
                    0pt \dimexpr \hsize-14mm\relax
                    0pt \dimexpr \hsize-14mm\relax
                    0pt \hsize},
                underlay unbroken and last={
                    \draw [#2!75!black,line width=.5mm](frame.south east)--++(180:\tcboxedtitlewidth-\pgflinewidth);
                }}}
        },
    }
}

\newtcolorbox[auto counter]{proposition}[2][]{%
    mystyle={blue}{Prop},
    mytitle={#2}{blue},
    #1}

\newtcolorbox[auto counter]{definition}[2][]{%
    mystyle={green}{Def},
    mytitle={#2}{green},
    #1}

\begin{document}
\pagestyle{empty}

\begin{definition}{}
A non-titled definition
\vspace{2.2cm}
\end{definition}

\begin{proposition}{A long title}
A titled proposition
\vspace{2cm}
\end{proposition}

\begin{definition}[height=2cm,label=Exlab]{A}
A titled definition
\end{definition}
\ref{Exlab}
\end{document}

Answer 1