编辑：现在我的问题是检测参数是否\mkbibnamegiven是单个首字母。我尝试这样做，l3regex但无法让它工作：
\documentclass{article}
\usepackage{lmodern}
\usepackage{xparse}
\usepackage{expl3}
\usepackage{l3regex}
\usepackage[style=authoryear]{biblatex}
\begin{filecontents*}{\jobname.bib}
@book{doe2016, author = {J. Doe}, date = {2016}}
@book{doe2017, author = {P. Doe}, date = {2017}}
@book{doe2015a, author = {John Doe}, date = {2015}}
@book{doe2015b, author = {James Doe}, date = {2015}}
\end{filecontents*}
\addbibresource{\jobname.bib}
\ExplSyntaxOn
\NewDocumentCommand{\IfInitial}{mmm}{%
\regex_match:nnTF{\w\.}{#1}{{\bfseries #2}}{#3}% Doesn't work
% \regex_match:nnTF{^\w.$}{#1}{{\bfseries #2}}{#3}% Also doesn't work
}
\ExplSyntaxOff
\renewcommand*{\mkbibnamefamily}[1]{\MakeLowercase{\scshape#1}}%
\renewcommand*{\mkbibnamegiven}[1]{
\ifnumequal{\value{uniquename}}{2}{%
\IfInitial{#1}{\MakeLowercase{\scshape#1}}{#1}%
}{%
\MakeLowercase{\scshape#1}%
}%
}
\begin{document}
\noindent\cite{doe2015a}\\
\cite{doe2015b}\\
\cite{doe2016}\\% This gives me J. Doe, but I want j. Doe
\cite{doe2017}
\end{document}
原始问题：
这是我提出的问题的延伸这里。
使用 BibLaTeX，我尝试在名字只是首字母时将其转换为小写字母，而在名字是全名时将其转换为正常字体。以下是我的尝试：
\documentclass{article}
\usepackage{lmodern}
\usepackage[style=authoryear]{biblatex}
\begin{filecontents*}{\jobname.bib}
@book{doe2016, author = {J. Doe}, date = {2016}}
@book{doe2017, author = {P. Doe}, date = {2017}}
@book{doe2015a, author = {John Doe}, date = {2015}}
@book{doe2015b, author = {James Doe}, date = {2015}}
\end{filecontents*}
\addbibresource{\jobname.bib}
\renewcommand*{\mkbibnamefamily}[1]{\MakeLowercase{\scshape#1}}%
\renewcommand*{\mkbibnamegiven}[1]{
\ifnumequal{\value{uniquename}}{2}{#1}{\MakeLowercase{\scshape#1}}%
}
\begin{document}
\noindent\cite{doe2015a}\\% First name is normal, like I want it
\cite{doe2015b}\\% First name is normal, like I want it
\cite{doe2016}\\% First name is normal, but I want it in small caps
\cite{doe2017}% First name is in small caps, like I want it
\end{document}
忽略小写字母，结果如下：
约翰·多伊 2015
詹姆斯·多伊 2015
J. doe 2016
页2017 年母鹿
然而我想要的是：
约翰·多伊 2015
詹姆斯·多伊 2015
j. 2016 年母鹿
页2017 年母鹿
由于年份不同，doe2016不需要全名，所以我们只获取首字母。但的值uniquename仍然是 2，就好像我们需要全名一样。那么，我该如何更改名字的格式，以适应仅打印首字母的情况？
答案1
它不起作用，因为#1是\namepartgiven，您需要扩展它才能获得其当前值。
\documentclass{article}
\usepackage{lmodern}
\usepackage{xparse}
\usepackage{expl3}
%\usepackage{l3regex} % not needed with a recent version
\usepackage[style=authoryear]{biblatex}
\begin{filecontents*}{\jobname.bib}
@book{doe2016, author = {J. Doe}, date = {2016}}
@book{doe2017, author = {P. Doe}, date = {2017}}
@book{doe2015a, author = {John Doe}, date = {2015}}
@book{doe2015b, author = {James Doe}, date = {2015}}
\end{filecontents*}
\addbibresource{\jobname.bib}
\ExplSyntaxOn
\NewDocumentCommand{\IfInitial}{mmm}
{
\regex_match:nVTF {\w\.} \namepartgiven {{\bfseries #2}} {#3}
}
\cs_generate_variant:Nn \regex_match:nnTF { nV }
\ExplSyntaxOff
\renewcommand*{\mkbibnamefamily}[1]{\MakeLowercase{\scshape#1}}%
\renewcommand*{\mkbibnamegiven}[1]{
\ifnumequal{\value{uniquename}}{2}{%
\IfInitial{#1}{\MakeLowercase{\scshape#1}}{#1}%
}{%
\MakeLowercase{\scshape#1}%
}%
}
\begin{document}
\noindent\cite{doe2015a}\\
\cite{doe2015b}\\
\cite{doe2016}\\% This gives me J. Doe, but I want j. Doe
\cite{doe2017}
\end{document}
