Biber/BibLaTex：如果缺少文献条目日期，如何将“nd”字母更改为自定义字母？

Question

我怎样才能将在缺少日期的情况下生成的“nd”字母更改为自定义字母（例如“o. J.”）？

---

最低工作示例：

% ==== PREAMBEL =============================================================

\documentclass{scrbook}

\usepackage[
                citestyle=numeric,
                style=authoryear,
                natbib=true,
                backend=biber
            ]{biblatex}            % Use Biber and BibLaTex instead of BibTex

\usepackage{filecontents}

% ==== BIBLIOGRAPHY ========================================================

\begin{filecontents}{\jobname.bib} 

@book{Doe,
    author = {Doe, Jon},
    title = {How to cite a literature-entry containing date},
    date = {2015},

}

@book{Dae,
    author = {Dae, Liz},
    title = {How to cite a literature-entry with missing date},
    date = {date},
}

\end{filecontents}

\bibliography{\jobname} 

% ==== DOCUMENT ============================================================

\begin{document}

\chapter{Experimental chapter}

    This is a text for testing how to cite a literature-entry containing date \parencite[look at][]{Doe}.

    This is a text for testing how to cite a literature-entry with missing date \parencite[look at][]{Dae}.

\printbibliography

\end{document}

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文内引用截图：

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参考书目截图：

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非常感谢您的帮助！

Answer 1

给你：

% ==== PREAMBEL =============================================================

\documentclass{scrbook}
\usepackage[utf8]{inputenc}
\usepackage[german]{babel}
\usepackage{csquotes} 
\usepackage[
    citestyle=numeric,
    style=authoryear,
    natbib=true,
    backend=biber
]{biblatex} % Use Biber and BibLaTex instead of BibTex

\usepackage{filecontents}

% ==== BIBLIOGRAPHY ========================================================

\begin{filecontents}{\jobname.bib}

@book{Doe,
author = {Doe, Jon},
title = {How to cite a literature-entry containing date},
date = {2015},

}

@book{Dae,
author = {Dae, Liz},
title = {How to cite a literature-entry with missing date},

% 日期 = {日期}, }

@online{Lear,
title ={Edward Lear Home Page},
url = {http://www.nonsenselit.org/Lear/pstories/cm/cm.html},
urldate = {2015-07-16},
}

\end{filecontents}

\addbibresource{\jobname.bib}

\DefineBibliographyStrings{german}{%
nodate = {{}o\adddot\addnbthinspace J\adddot}
    }%
\DeclareLabeldate{%
\field{date}
\field{eventdate}
\field{origdate}
\literal{nodate}
}

%
\renewbibmacro*{date+extrayear}{%
\iffieldundef{\thefield{datelabelsource}year}
{\printtext[parens]{\printfield{labelyear}}}
{\printtext[parens]{%
\printfield{\thefield{datelabelsource}year}%
\printfield{extrayear}}}}% ==== DOCUMENT ============================================================

\begin{document}

\chapter{Experimental chapter}

This is a text for testing how to cite a literature-entry containing date \parencite[look at][]{Doe}.

This is a text for testing how to cite a literature-entry with missing date \parencite[look at][]{Dae}.

Edward Lear revisited Roman history \parencite[look at]{Lear}

\printbibliography

\end{document}