如何更改 circuitikz 中某些元件标签的颜色？

Question

我尝试查看这些先前的帖子来解决我的问题：

1. 为当前箭头着色
2. 为当前标签着色

这些帖子提出的解决方案似乎重新编程了图中所有电流的颜色。我试图做的是选择性地改变图表上电流箭头的颜色。在下面的网络中，我试图将整个 I1(t) 箭头涂成红色（在我的 MWE 中，不仅仅是箭头尖端被涂成颜色），并将 Ic(t) 保留为黑色，包括箭头尖端。

    \documentclass{standalone}
    \usepackage{circuitikz}

    \makeatletter
    \ctikzset{current arrow color/.initial=black}% create key

    \pgfdeclareshape{currarrow}{
    \anchor{center}{
    \pgfpointorigin
    }
    \anchor{tip}{
    \pgfpointorigin
        \pgf@circ@res@step = \pgf@circ@Rlen
            \divide \pgf@circ@res@step by 16
    \pgf@x  =\pgf@circ@res@step
    }
\behindforegroundpath{      

    \pgfscope
        \pgf@circ@res@step = \pgf@circ@Rlen
        \divide \pgf@circ@res@step by 16

        \pgfpathmoveto{\pgfpoint{-.7\pgf@circ@res@step}{0pt}}
        \pgfpathlineto{\pgfpoint{-.7\pgf@circ@res@step}{-.8\pgf@circ@res@step}}
        \pgfpathlineto{\pgfpoint{1\pgf@circ@res@step}{0pt}}
        \pgfpathlineto{\pgfpoint{-.7\pgf@circ@res@step}{.8\pgf@circ@res@step}}
        \pgfpathlineto{\pgfpoint{-.7\pgf@circ@res@step}{0pt}}           
        \pgfsetcolor{\pgfkeysvalueof{/tikz/circuitikz/current arrow color}}
        \pgfusepath{draw,fill}

    \endpgfscope
    }
    }
    \makeatother

    \begin{document}

    \ctikzset{voltage/distance from node=.8}

    \begin{circuitikz}[american]
    \draw[circuitikz/current arrow color=red]
    % bottom line           
       (0,0) to [short, o-] (9,0)
        % shunt branches            
       (2,0) to [C, *-*,l={$C/2$},v=$V_C$,f>^=$I_C(t)$] (2,3)
       (9,0) to [C, *-*,l=$C/2$,n=C2] (9,3)     
        % top line          
       (0,3) to [short,o-] (3,3)
       to [R, l_=$R_1$,i={\color{\pgfkeysvalueof{/tikz/circuitikz/current arrow color}}$I_1$},f>^=$\color{red}I_1(t)$] (9,3)
     % Input and output labels
     (C2.s)  node[right] {$V_s$};% anchors rotated
    \end{circuitikz}
    \end{document}

Answer 1

这也会修改flowarrow形状，并将图表拆分为两个图。（如果我没记错的话，您无法使用内联范围更改颜色。）

\documentclass{standalone}
\usepackage{circuitikz}

\makeatletter
\ctikzset{current arrow color/.initial=black}% create key

\let\old@circ@drawcurrent=\pgf@circ@drawcurrent
\def\pgf@circ@drawcurrent{\old@circ@drawcurrent}

\pgfdeclareshape{currarrow}{
\anchor{center}{
\pgfpointorigin
}
\anchor{tip}{
\pgfpointorigin
    \pgf@circ@res@step = \pgf@circ@Rlen
        \divide \pgf@circ@res@step by 16
\pgf@x  =\pgf@circ@res@step
}
\behindforegroundpath{      

\pgfscope
    \pgf@circ@res@step = \pgf@circ@Rlen
    \divide \pgf@circ@res@step by 16

    \pgfpathmoveto{\pgfpoint{-.7\pgf@circ@res@step}{0pt}}
    \pgfpathlineto{\pgfpoint{-.7\pgf@circ@res@step}{-.8\pgf@circ@res@step}}
    \pgfpathlineto{\pgfpoint{1\pgf@circ@res@step}{0pt}}
    \pgfpathlineto{\pgfpoint{-.7\pgf@circ@res@step}{.8\pgf@circ@res@step}}
    \pgfpathlineto{\pgfpoint{-.7\pgf@circ@res@step}{0pt}}           
    \pgfsetcolor{\pgfkeysvalueof{/tikz/circuitikz/current arrow color}}
    \pgfusepath{draw,fill}

\endpgfscope
}
}
\pgfdeclareshape{flowarrow}{
    \anchor{center}{\pgfpointorigin}
    \anchor{tip}{
    \pgfpointorigin
        \pgf@circ@res@step = \pgf@circ@Rlen
            \divide \pgf@circ@res@step by 16
    \pgf@x  =\pgf@circ@res@step
    }
\behindforegroundpath{
    \pgfscope
        \pgf@circ@res@step = \pgf@circ@Rlen
        \divide \pgf@circ@res@step by 4
        \pgfpathmoveto{\pgfpoint{-\pgf@circ@res@step}{0pt}}
        \pgfpathlineto{\pgfpoint{\pgf@circ@res@step}{0pt}}
        %\pgfsetcolor{\pgfkeysvalueof{/tikz/circuitikz/color}}
  \pgfsetcolor{\pgfkeysvalueof{/tikz/circuitikz/current arrow color}}
        \pgfusepath{draw}
        \pgftransformshift{\pgfpoint{\pgf@circ@res@step}{0pt}}
        \pgfnode{currarrow}{tip}{}{}{\pgfusepath{fill}}
    \endpgfscope
}
}
\makeatother

\begin{document}

\ctikzset{voltage/distance from node=.8}

\begin{circuitikz}[american]
\draw[circuitikz/current arrow color=black]
% bottom line           
   (0,0) to [short, o-] (9,0)
    % shunt branches            
   (2,0) to [C, *-*,l={$C/2$},v=$V_C$,f>^=$I_C(t)$] (2,3)
   (9,0) to [C, *-*,l=$C/2$,n=C2] (9,3)     
    % top line          
   (0,3) to [short,o-] (3,3);
\draw[circuitikz/current arrow color=red] (3,3)
   to [R, l_=$R_1$,i={$\color{red}I_1$},f>^=$\color{red}I_1(t)$] (9,3)
 % Input and output labels
 (C2.s)  node[right] {$V_s$};% anchors rotated
\end{circuitikz}
\end{document}