Making authoryear citation style bold with biblatex

biblatex

My university authority requires a bold author-year citation style with also a bold bibliography author-year style including the author(s) and year
I am not an expert in biblatex and need your help. Included a minimum working example but without any attempts to apply what is required.

\documentclass[british]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{libertine}
\usepackage{babel}
\usepackage{csquotes}
\usepackage[style=authoryear,citestyle=authoryear,backend=biber]{biblatex}
\usepackage[pdfborder={0 0 0},pdfborderstyle={}]{hyperref}
%=====================================================
\usepackage{filecontents}
\begin{filecontents}{\mybib.bib}
@Article{caton1989periodontal,
  author  = {Caton, J},
  title   = {Periodontal diagnosis and diagnostic aids: consensus report in Proceedings of the World Workshop in Clinical Periodontics},
  journal = {American Academy of Periodontology},
  year    = {1989},
}
@Book{williams1992pathology,
  author    = {Williams, D.M.},
  title     = {Pathology of Periodontal Disease},
  isbn      = {9780192621207},
  publisher = {Oxford University Press},
  series    = {Oxford medical publications},
  url       = {https://books.google.com.eg/books?id=DbVtQgAACAAJ},
  lccn      = {91027234},
  year      = {1992},
}
\end{filecontents}
\addbibresource{\mybib.bib}

\begin{document}
Periodontitis is a chronic multifactorial inflammatory disease \parencite{caton1989periodontal}.
Periodontal disease is the most common oral condition of human population
\parencite{williams1992pathology}.

\printbibliography
\end{document}

Best Answer

If you switch from the standard authoryear style to biblatex-ext's ext-authoryear, a solution can look like this

\documentclass[british]{article}
\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage{libertine}
\usepackage{babel}
\usepackage{csquotes}
\usepackage[style=ext-authoryear, backend=biber]{biblatex}
\usepackage{hyperref}

\newrobustcmd*{\mkboldoutercitedelims}[1]{%
  \mkbibbold{%
    \mkoutercitedelims{#1}}}

\DeclareCiteCommand{\cite}[\mkboldoutercitedelims]
  {\usebibmacro{prenote}}%
  {\usebibmacro{citeindex}%
   \usebibmacro{cite}}
  {\multicitedelim}
  {\usebibmacro{postnote}}

\DeclareCiteCommand*{\cite}[\mkboldoutercitedelims]
  {\usebibmacro{prenote}}%
  {\usebibmacro{citeindex}%
   \usebibmacro{citeyear}}
  {\multicitedelim}
  {\usebibmacro{postnote}}

\DeclareMultiCiteCommand{\cites}[\mkboldoutercitedelims]{\cite}{\multicitedelim}

\newrobustcmd*{\mkboldouterparencitedelims}[1]{%
  \mkbibbold{%
    \mkouterparencitedelims{#1}}}

\DeclareCiteCommand{\parencite}[\mkboldouterparencitedelims]
  {\usebibmacro{prenote}}%
  {\usebibmacro{citeindex}%
   \usebibmacro{cite}}
  {\multicitedelim}
  {\usebibmacro{postnote}}

\DeclareCiteCommand*{\parencite}[\mkboldouterparencitedelims]
  {\usebibmacro{prenote}}
  {\usebibmacro{citeindex}%
   \usebibmacro{citeyear}}
  {\multicitedelim}
  {\usebibmacro{postnote}}

\DeclareMultiCiteCommand{\parencites}[\mkboldouterparencitedelims]{\parencite}{\multicitedelim}

\newrobustcmd*{\mkboldoutertextcitedelims}[1]{%
  \mkbibbold{%
    \mkoutertextcitedelims{#1}}}

\DeclareCiteCommand{\textcite}[\mkboldoutertextcitedelims]
  {\boolfalse{cbx:parens}}
  {\usebibmacro{citeindex}%
   \iffirstcitekey
     {\setcounter{textcitetotal}{1}}
     {\stepcounter{textcitetotal}%
      \textcitedelim}%
   \usebibmacro{textcite}}
  {\ifbool{cbx:parens}
     {\bibcloseparen\global\boolfalse{cbx:parens}}
     {}}
  {\usebibmacro{textcite:postnote}}

\DeclareMultiCiteCommand{\textcites}[\mkboldoutertextcitedelims]{\textcite}{}

\DeclareNameWrapperFormat{sortname}{\mkbibbold{#1}}
\DeclareFieldFormat{biblabeldate}{\mkbibbold{\mkbibparens{#1}}}

\addbibresource{biblatex-examples.bib}

\begin{document}
Lorem \autocite{sigfridsson}
ipsum \autocite{worman}

\printbibliography
\end{document}

"Lorem (Sigfridsson and Ryde 1998) ipsum (Worman 2002)" with citations in bold.
Name and year are also bold in the bibliography.

The original definitions of the citations can be found in ext-authoryear.cbx. Basically we just injected an \mkbibbold into the outer delimiter wrapper commands.

For the bibliography we used the name wrapper format sortname and biblatex-ext's biblabeldate format for the year.