\clearfield 不适用于条目集

Question 1

您可以改用源映射：

\DeclareSourcemap{
  \maps[datatype=bibtex]{
    \map{
      \step[fieldset=month,null]
    }
  }
}

在全：

\documentclass[10pt]{article}

\usepackage[hyperref,backend=biber,maxnames=2,style=nature,articletitle=false,
isbn=false]{biblatex}
\usepackage{hyperref}
\usepackage{filecontents}

\begin{filecontents}{\jobname.bib}
@article{key1,
author = {Author, A.},
year = {2001},
month = {3},
title = {Title},
publisher = {Publisher},
}
@article{key2,
author = {Author, B.},
year = {2002},
month = {2},
title = {Title},
publisher = {Publisher},
}
@article{key3,
author = {Author, C.},
year = {2003},
month = {1},
title = {Title},
publisher = {Publisher},
}
\end{filecontents}

\addbibresource{\jobname.bib}

\DeclareSourcemap{
  \maps[datatype=bibtex]{
    \map{
      \step[fieldset=month,null]
    }
  }
}

\begin{document}

\defbibentryset{set1}{key1,key2}
\cite{set1}
\cite{key3}

\printbibliography

\end{document}

Answer

您可以改用源映射：

\DeclareSourcemap{
  \maps[datatype=bibtex]{
    \map{
      \step[fieldset=month,null]
    }
  }
}

在全：

\documentclass[10pt]{article}

\usepackage[hyperref,backend=biber,maxnames=2,style=nature,articletitle=false,
isbn=false]{biblatex}
\usepackage{hyperref}
\usepackage{filecontents}

\begin{filecontents}{\jobname.bib}
@article{key1,
author = {Author, A.},
year = {2001},
month = {3},
title = {Title},
publisher = {Publisher},
}
@article{key2,
author = {Author, B.},
year = {2002},
month = {2},
title = {Title},
publisher = {Publisher},
}
@article{key3,
author = {Author, C.},
year = {2003},
month = {1},
title = {Title},
publisher = {Publisher},
}
\end{filecontents}

\addbibresource{\jobname.bib}

\DeclareSourcemap{
  \maps[datatype=bibtex]{
    \map{
      \step[fieldset=month,null]
    }
  }
}

\begin{document}

\defbibentryset{set1}{key1,key2}
\cite{set1}
\cite{key3}

\printbibliography

\end{document}

Question 2

gusbrs 已经给出了更可取的答案，所以让我解释一下导致这种行为的原因，并提供一个替代的（但较差的）解决方案。源映射解决方案是可取的，因为它在到达之前就删除了字段信息biblatex，而\clearfieldBiber 会读取和处理字段，并且只在最后一刻打印时抑制字段。如果清除的字段与排序、唯一性、标签...字段解析或其他高级功能相关，这可能会导致输出差异。如果使用源映射，则在任何上述函数启动之前都会有效地删除该字段，但是如果您使用\clearfield这些函数，则所有函数都会尊重并根据字段的存在采取行动。该month字段可用于排序，在这种情况下，至关重要的是 Biber 会将其删除，以便文档不会随机对同一年的条目进行排序。另一个示例是，如果不存在其他日期，则urldate可以将其用作后备，如果您想抑制它，它不应该凭借作为的来源潜入您的参考书目，这只能通过在源映射中删除该字段来防止。labeldateurldatelabeldate

请看以下示例。正如您所看到的，红色 X 的存在\AtEveryBibitem会在参考书目中每个项目的开头执行一次，此时标记为灰色的条目键处于范围内并正在处理中。特别是，红色 X 不会对集合的所有成员重复出现。

您将会看到，对于集合，范围内的条目是set1，因此如果在那里发出，则只会删除元条目的\clearfield{month}（已经不存在的）字段，而不是其元素。monthset1

集合由特殊驱动程序@set和命令处理\entryset。\entryset通过调用各自的驱动程序，循环对集合成员进行排版。我们可以将添加\clearfield{month}到预代码中\entryset，以删除集合成员的月份。在正确的范围内（参见黄色 Y 后的蓝色输入键），对每个集合成员（参见下面的黄色 Y）执行一次预代码。

对于条目，我们可以观察到类似的效果related：在\AtEveryBibitem对主条目执行时，所有related条目都不会受到影响。

\documentclass[10pt]{article}
\usepackage{xcolor}
\usepackage[backend=biber, maxnames=2,style=nature, articletitle=false, isbn=false]{biblatex}

\AtEveryBibitem{%
  \textcolor{red}{X}%                     only for demonstration
  \textcolor{gray}{\thefield{entrykey}}%  only for demonstration
  \clearfield{month}}

\DeclareBibliographyDriver{set}{%
  \entryset
    {\clearfield{month}%
     \textcolor{yellow}{Y}%                 for illustrative purposes only
     \textcolor{gray}{\thefield{entrykey}}% for illustrative purposes only
     \ifbool{bbx:subentry}
       {\printfield[bibentrysetcount]{entrysetcount}%
        \printunit*{\addnbspace}}
       {}}
    {}%
  \newunit\newblock
  \usebibmacro{setpageref}%
  \finentry}

\usepackage{filecontents}
\begin{filecontents}{\jobname.bib}
@article{key1,
  author = {Author, A.},
  year = {2001},
  month = {3},
  title = {Title},
  publisher = {Publisher},
}
@article{key2,
  author = {Author, B.},
  year = {2002},
  month = {2},
  title = {Title},
  publisher = {Publisher},
}
@article{key3,
  author = {Author, C.},
  year = {2003},
  month = {1},
  title = {Title},
  publisher = {Publisher},
}
\end{filecontents}
\addbibresource{\jobname.bib}

\begin{document}
\defbibentryset{set1}{key1,key2}
\cite{set1}
\cite{key3}

\printbibliography
\end{document}

Answer