[mapserver-users] Changing map colors dynamically doesn't work

[Michael Wessel]

Hi Jeff, 

On Sunday 02 March 2008 16:59, Jeff McKenna wrote:
> See the "URL Configuration Changes" section of:
> http://trac.osgeo.org/mapserver/browser/branches/branch-5-0/mapserv
>er/MIGRATION_GUIDE.TXT

Great, that works! Thanks a lot!

And here is the next problem - how would I change the class expression

 CLASS
      EXPRESSION (1)
      STYLE
        COLOR        255 255 1
        OUTLINECOLOR 32 32 32
      END
    END

"1" is for true, so all polygons are selected; I now want to change 
the expression to (0) (= false), in order to deselect all polygons. 

I tried: 

map.layer[lakes].class[0].expression[0]='(0)'

and got: 

loadClass(): Unknown identifier. Parsing error near ((0)):(line 1)

And for 

map.layer[lakes].class[0]='expression+(0)'

I get

loadClass(): Unknown identifier. Parsing error near (expression (0)):
(line 1) 


Moreover, for 

map.layer[lakes].class[expression]='(0)'

msUpdateMapFromURL(): General error message. Class to be modified not 
valid.

Anyone knows the correct syntax for changing this expression via the 
URL? 

Thanks for the great support, 


Michael