How to add a comma between journal and volume

Question

I have to customize this biblatex style as follows: there should be a comma between the name of the journal and its volume. How could I do that?

\documentclass[12pt,a4paper]{article}
\usepackage[T1]{fontenc}
\usepackage[french]{babel}
\usepackage[backend=biber, style=ext-verbose, articlein=false]{biblatex}
\usepackage{hyperref}

\DeclareDelimFormat[bib]{nametitledelim}{\addcomma\space}
\DeclareFieldFormat[article,inbook,incollection,inproceedings,patent,thesis,unpublished]   {title}{#1\isdot}


\begin{filecontents}{\jobname.bib}

@Article{Chiantaretto2005,
author = {Chiantaretto, Jean-François}, 
title = {À propos de la première transgression}, 
journal = {Topique}, 
volume = {92}, 
number = {3}, 
pages = {111--125}, 
year = {2005}, 
}
\end{filecontents}
\addbibresource{\jobname.bib}

\begin{document}
Some text here \autocite{Chiantaretto2005}.

\printbibliography
\end{document}

Answer 1

The biblatex-ext styles have a delimiter called \jourvoldelim to controll the punctuation between the journal and the volume (see the biblatex-ext docs, §5.2 Punctuation, p. 27 in v0.18).

\documentclass[12pt,a4paper]{article}
\usepackage[T1]{fontenc}
\usepackage[french]{babel}
\usepackage[backend=biber, style=ext-verbose, articlein=false]{biblatex}
\usepackage{hyperref}

\DeclareDelimFormat[bib]{nametitledelim}{\addcomma\space}
\DeclareFieldFormat[article,inbook,incollection,inproceedings,patent,thesis,unpublished]
  {title}{#1\isdot}

\renewcommand*{\jourvoldelim}{\addcomma\space}

\begin{filecontents}{\jobname.bib}
@article{Chiantaretto2005,
  author  = {Chiantaretto, Jean-François},
  title   = {À propos de la première transgression},
  journal = {Topique},
  volume  = {92},
  number  = {3},
  pages   = {111--125},
  year    = {2005},
}
\end{filecontents}
\addbibresource{\jobname.bib}

\begin{document}
Some text here \autocite{Chiantaretto2005}.

\printbibliography
\end{document}