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

2017-08-09 17:37 GMT+02:00 Pablo Rodriguez <oinos@gmx.es>:

> On 08/09/2017 05:05 PM, Fabrice Couvreur wrote:
> > I want topspace=bottomspace=2cm
> > It works for topspace but not for bottomspace
> > How to do ?
>
> Hi Fabrice,
>
> is this what you intend?
>
>     \showframe
>     \setuplayout
>       [header=26pt,
>        headerdistance=25pt,
>        backspace=2cm,
>        width=middle,
>        topspace=\dimexpr 2cm-\headerheight-\headerdistance\relax,
>        footer=16pt,
>        height=middle]
>        %~ bottomspace=\dimexpr 2cm-\footerheight-\footerdistance\relax]
>     \starttext
>     \ConTeXt.
>     \stoptext
>
> Just in case it helps,
>
> Pablo
> --
> http://www.ousia.tk
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