[mapserver-users] Redraw only one layer

[mmypost mmypost]

Hi
Sorry for my bad English.

I use mapscript for .Net.
I have a some layers:
  layer1: off
  layer2: off
  layer3: on
  layer4: on
......
 layer_N: on
 
I turn on layer1 and mapserver very long time  redraw map.
I turn on layer2 and mapserver very long time  redraw map again.
I think, that mapserver redraw all layers every time.

How I can force mapserver(by mapscript) draw only one layer (layer1 or layer2) if extent not changed and other layers not changed.

Yours sincerely,
Sev