Display DOI in DeclareCiteCommand

Question

I would like to display DOI with \DeclareCiteCommand. I'm using \documentclass{report}.

I tried this:

\documentclass{article}
\usepackage[backend=biber, sorting=none]{biblatex}
\addbibresource{references.bib}
\DeclareCiteCommand{\mycite}%
{
    \usebibmacro{prenote}\addspace
}%
{%
    \mkbibquote{\thefield{title}}%
    \addcomma\addspace by \printnames[][-\value{listtotal}]{author}%
    \addcomma\addspace \thefield{year}%
    \addcomma\addspace \mkbibitalic{\thefield{journaltitle}}%
    \addcomma\addspace \mkbibitalic{\thefield{volume}}%
    \mkbibparens{\thefield{number}}%
    \addcomma\addspace%
}
{}
{
    \usebibmacro{postnote}%
    \addspace%
    \mkbibparens{\url{\thefield{doi}}}%
    \adddot%
}
\begin{document}
\mycite{sampleentry}
\end{document}

In the bibliography, I put this entry found in "Publication Manual of the American Psychological Association, Seventh Edition (2020)":

@article{sampleentry,
    author      =   {Wang, Xiaoye and Lind, Mats and Bingham, Geoffrey},
    year        =   {2018},
    month       =   {06},
    pages       =   {1513},
    title       =   {Large Continuous Perspective Change With Noncoplanar Points Enables Accurate Slant Perception},
    volume      =   {44},
    number      =   {10},
    journal     =   {Journal of Experimental Psychology: Human Perception and Performance},
    doi         =   {https://doi.org/10.1037/xhp0000553},
}

However, I only get \thefield{doi}. Is there another command to print the DOI?

Answer 1

You shouldn't have to use \thefield for printing. Instead use \printfield and friends or even better pre-defined bibmacros that print whole chunks of the data you want to show. You should also not have bare \addcomma\addspaces flying around. Those should be inside \setunits to make use of biblatex's punctuation buffer.

As shown the macro also risks introducing massive amount of undesirable space.

I suggest the following approach, where \printfield{doi} to print the DOI works perfectly fine.

Logically, however, it is a bit unusual and possibly risky to print entry data in the "postnote" code: If you cite multiple entries you end up with the data from the last key. The others are ignored. It might be more logical to move all printing into the loopcode and possibly warn if more than one entry is cited.

\documentclass[british]{article}
\usepackage[T1]{fontenc}
\usepackage{babel}
\usepackage{csquotes}
\usepackage[backend=biber, style=authoryear]{biblatex}
\DeclareFieldFormat{ccdoi}{%
  \mkbibparens{%
    \ifhyperref
      {\href{https://doi.org/#1}{\nolinkurl{https://doi.org/#1}}}
      {\nolinkurl{https://doi.org/#1}}}}
\DeclareCiteCommand{\CustomCite}
  {\usebibmacro{prenote}}
  {\printfield{title}%
   \setunit{\addcomma\space}%
   \bibstring{byauthor}%
   \setunit{\addspace}%
   \printnames[default]{author}%
   \setunit{\addcomma\space}%
   \printdate
   \setunit{\addcomma\space}%
   \usebibmacro{journal+issuetitle}}
  {\multicitedelim}
  {\usebibmacro{postnote}%
   \setunit{\addspace}%
   \printfield[ccdoi]{doi}}
\addbibresource{biblatex-examples.bib}
\begin{document}
Lorem \autocite{sigfridsson}
\CustomCite{sigfridsson}
\CustomCite[381]{sigfridsson}
\printbibliography
\end{document}

---

The problem in the updated code was

\url{\thefield{doi}}

Depending on the definition \url reads and prints its argument almost verbatim. In this case this means that the output that it produces is \thefield{doi}, which is not what you want. (\mkbibparens{\thefield{doi}} instead of \mkbibparens{\url{\thefield{doi}}} would have produced output more to your liking. But you would have gotten into trouble with hyphenation and linking, so this is definitely not recommended.) Again, you want to use \printfield{doi} instead, because that uses \url (and friends) in the correct way.

Answer 2

It seems that no command can be used in the postnote part.

\DeclareCiteCommand{\CustomCite}
{
    \usebibmacro{prenote}\addspace
}
{%
    \mkbibquote{\thefield{title}}%
    \addcomma\addspace by \printnames[][-\value{listtotal}]{author} %
    \addcomma\addspace \thefield{year} %
    \addcomma\addspace \mkbibitalic{\thefield{journaltitle}} %
    \addcomma\addspace \mkbibitalic{\thefield{volume}} %
    \mkbibparens{\thefield{number}} %
    \addcomma \addspace %
    \mkbibparens{\thefield{doi}} %
}
{}
{
    \usebibmacro{postnote} %
    \adddot %
}