How to change "url" to "Available at" for citing a website in BibLatex?

Question

This is another question related to the first question which is How to add authorship for citing a website in BibLatex?

The format in BibLatex is

url

I want to have

Available at

Basically, I want to change from:

to

I am using:

@online{WinNT,
%   author = {Conflict Memory Displacement},
   author = {{Conflict Memory Displacement}},
   title = {Conflict Memory Displacement: Responding to the refugee crisis in the UK and Italy.},
   year = 2016,
   url = {http://conflictmemorydisplacement.com/},
%   urldate = {28 July 2016}
   addendum = "[Accessed 28 July 2016]",
  }

My full MWE (I did not have any setting for @online and do not want to disturb other settings in citting.

\documentclass{article}
\usepackage{xpatch}
% \usepackage[style = authoryear-comp, maxnames = 99]{biblatex}

\usepackage[backend=biber, 
% style=authoryear, 
 style=authoryear-comp,
% citestyle=authoryear, 
dashed=false,
maxcitenames=2,
maxbibnames=99,
giveninits,
uniquename=init]{biblatex}


\DeclareNameAlias{sortname}{family-given} %for second and third author name
\DeclareFieldFormat{postnote}{\printtext[bibhyperref]{#1}}

\usepackage[T1]{fontenc}
\usepackage[utf8]{inputenc}
\usepackage[english]{babel}

\usepackage{csquotes}

\usepackage[unicode,colorlinks,citecolor=blue]{hyperref}


% for a chapter edited by a book
\usepackage{xpatch}
% \renewcommand*{\finalnamedelim}{\addspace\&\space} 
% \renewcommand*{\intitlepunct}{\space} (to become In:)
\renewcommand{\labelnamepunct}{\space} %to delete . after (1997)
% \DeclareFieldFormat[article, incollection, unpublished]{pages}{#1} % to add in PP. (page)
\DeclareFieldFormat[article, incollection, unpublished]{title}{#1}
% \renewcommand{\bibpagespunct}{\ifentrytype{article}{\addcolon}{\addperiod\addspace}} %cancel out this in order to add in PP. (page)


% for title italic
% \DeclareFieldFormat*{title}{\mkbibemph{#1}} %for title italic in all format (conference, paper..)
\DeclareFieldFormat*{title}{#1} %for conference title delete ".."
\DeclareFieldFormat[incollection]{title}{\mkbibemph{#1}} %for incollecion title italic ONLY
\DeclareFieldFormat[thesis]{title}{\mkbibemph{#1}} %for phdthesis title italic ONLY
% for title italic

% to delete "In:" for article
\renewbibmacro{in:}{%
  \ifentrytype{article}{}{\printtext{\bibstring{in}\intitlepunct}}}
% to delete "In:" for article


% for delete comma after Author A and Aurhor b
\DefineBibliographyExtras{english}{%
   \let\finalandcomma\empty
   \let\finalandsemicolon\empty
 }
\renewcommand{\compcitedelim}{\space\&\space}
\DeclareNameAlias{editorin}{given-family}

\newbibmacro*{byeditor:in}{%
  \ifnameundef{editor}
    {}
    {\printnames[editorin]{editor}%
     \setunit{\addcomma\space}%
     \usebibmacro{editorstrg}%
     \clearname{editor}}}     


\xpatchbibdriver{inbook}
  {\usebibmacro{in:}%
   \usebibmacro{bybookauthor}%
   \newunit\newblock
   \usebibmacro{maintitle+booktitle}%
   \newunit\newblock
   \usebibmacro{byeditor+others}}
  {\usebibmacro{in:}%
   \usebibmacro{bybookauthor}%
   \newunit\newblock
   \usebibmacro{byeditor:in}%
   \newunit\newblock
   \usebibmacro{maintitle+booktitle}%
   \newunit\newblock
   \usebibmacro{byeditor+others}}
  {}{}

\xpatchbibdriver{incollection}
  {\usebibmacro{in:}%
   \usebibmacro{maintitle+booktitle}%
   \newunit\newblock
   \usebibmacro{byeditor+others}}
  {\usebibmacro{in:}%
   \usebibmacro{byeditor:in}%
   \setunit{\labelnamepunct}\newblock
   \usebibmacro{maintitle+booktitle}%
   \newunit\newblock
   \usebibmacro{byeditor}}
  {}{}

\xpatchbibdriver{inproceedings}
  {\usebibmacro{in:}%
   \usebibmacro{maintitle+booktitle}%
   \newunit\newblock
   \usebibmacro{event+venue+date}%
   \newunit\newblock
   \usebibmacro{byeditor+others}}
  {\usebibmacro{in:}%
   \usebibmacro{byeditor:in}%
   \setunit{\labelnamepunct}\newblock
   \usebibmacro{maintitle+booktitle}%
   \newunit\newblock
   \usebibmacro{event+venue+date}%
   \newunit\newblock
   \usebibmacro{byeditor+others}}
  {}{}

\xpatchbibdriver{phdthesis}
  {\usebibmacro{in:}%
   \usebibmacro{maintitle+booktitle}%
   \newunit\newblock
   \usebibmacro{event+venue+date}%
   \newunit\newblock
   \usebibmacro{byeditor+others}}
  {\usebibmacro{in:}%
   \usebibmacro{byeditor:in}%
   \setunit{\labelnamepunct}\newblock
   \usebibmacro{maintitle+booktitle}%
   \newunit\newblock
   \usebibmacro{event+venue+date}%
   \newunit\newblock
   \usebibmacro{byeditor+others}}
  {}{}

\DeclareDelimFormat[textcite]{postnotedelim}{\addcolon\space}
\DeclareDelimFormat[parencite]{postnotedelim}{\addcolon\space}

% \DeclareFieldFormat{postnote}{#1}
\DeclareFieldFormat{postnote}{\printtext[bibhyperref]{#1}}
\DeclareFieldFormat{multipostnote}{#1}


% for references 's studies (year)
\renewcommand*{\nameyeardelim}{\addcomma\space}
\newcommand{\mycite}[1]{\citeauthor{#1}'s \citeyear{#1}}

\DeclareCiteCommand{\citeauthor}
  {\boolfalse{citetracker}%
   \boolfalse{pagetracker}%
   \usebibmacro{prenote}}
  {\ifciteindex
     {\indexnames{labelname}}
     {}%
   \printtext[bibhyperref]{\printnames{labelname}}}
  {\multicitedelim}
  {\usebibmacro{postnote}}

\DeclareCiteCommand{\citeyear} % <======================================
    {}
    {(\bibhyperref{\printdate})}
    {\multicitedelim}
    {}

\DeclareCiteCommand{\parencite}[\mkbibparens]
  {\renewcommand*{\postnotedelim}{\addcolon\space}%
   \usebibmacro{cite:init}%
   \usebibmacro{prenote}}
  {\usebibmacro{citeindex}%
   \printtext[bibhyperref]{\usebibmacro{cite}}}
  {\multicitedelim}
  {\usebibmacro{postnote}}

\DeclareCiteCommand{\cbx@textcite}
  {\renewcommand*{\postnotedelim}{\addsemicolon\space}%
   \usebibmacro{cite:init}}
  {\usebibmacro{citeindex}%
   \usebibmacro{textcite}}
  {}
  {\usebibmacro{textcite:postnote}}  



\makeatletter
\let\abx@macro@textciteOrig\abx@macro@textcite
\renewbibmacro{textcite}{% <============================================
   \bibhyperref{%
   \let\bibhyperref\relax\relax%
   \abx@macro@textciteOrig%
   }%
}%
\makeatother
% for references 's studies (year)



\usepackage{filecontents}
\begin{filecontents*}{\jobname.bib}




@online{WinNT,
%   author = {Conflict Memory Displacement},
   author = {{Conflict Memory Displacement}},
   title = {Conflict Memory Displacement: Responding to the refugee crisis in the UK and Italy.},
   year = 2016,
   url = {http://conflictmemorydisplacement.com/},
%   urldate = {28 July 2016}
   addendum = "[Accessed 28 July 2016]",
  }

@book{latexcompanion,
    author    = "Michel Goossens and Frank Mittelbach and Alexander Samarin",
    title     = "The \LaTeX\ Companion",
    year      = "1993",
    publisher = "Addison-Wesley",
    address   = "Reading, Massachusetts"
}


\end{filecontents*}
\addbibresource{\jobname.bib}

\begin{document}
\nocite{*}

This website is done \parencite{WinNT}.\\
This book is done byford \textcite{latexcompanion}



\printbibliography
\end{document}

Answer 1

This string is hardcoded in biblatex.def: \DeclareFieldFormat{url}{\mkbibacro{URL}\addcolon\space\url{#1}}. So you need to change it in your preamble like this:

\DeclareFieldFormat{url}{Available at\addcolon\space\url{#1}} Result:

Answer 2

If possible I would try and use biblatex's bibstrings instead of hard-coded text in field formats. The bibstring urlfrom is translated as "available from" in English, so it seems like the natural choice here.

\documentclass[british]{article}
\usepackage[T1]{fontenc}
\usepackage{babel}
\usepackage{csquotes}

\usepackage[style=authoryear-comp, backend=biber]{biblatex}

\DefineBibliographyStrings{english}{%
  urlfrom = {available at},
}

\DeclareFieldFormat{url}{\bibstring{urlfrom}\addcolon\space\url{#1}}

\addbibresource{biblatex-examples.bib}
\begin{document}
\cite{markey}
\printbibliography
\end{document}