Hi Pablo
Thank you very much. By combining the two codes, you get what I want.
Fabrice
"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
\switchtobodyfont[11pt]
\definelayout
[noheader]
[header=26pt,
headerdistance=25pt,
backspace=2cm,
width=middle,
topspace=\dimexpr 2cm-\headerheight-\headerdistance\relax,
footer=16pt,
height=middle]
\setuplayout
[header=\zeropoint,
headerdistance=25pt,
backspace=2cm,
width=middle,
topspace=\dimexpr 2cm-\headerheight-\headerdistance\relax,
footer=16pt,
height=middle]
\definelayout[1][noheader]
\setuppagenumbering
[alternative=,
location={footer,right]
\setupbackgrounds[header][text]
[frame=off,
bottomframe=on,
framecolor=gray,
rulethickness=2pt]
\defineframed[headerframed]
[frame=off,
location=depth,
bottomoffset=\lineheight,
align=middle,
width=fit]
\setupheadertexts[\headerframed{\ss\sc\bf\red Contrôle n\high{o}\,1 \\ }]
\setupheadertexts
[\headerframed{\tfx\ss Lycée JANSON DE SAILLY\\ 31 juillet 2017}]
[\headerframed{\tfx\ss T\high{le} ES 2 \\ Durée 1 heure 30}]
\starttext
\dorecurse{10}{\input knuth}
\stoptext