Different banner on each forum

[DPSR]

Hello Friends,

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I just want to show a ad banner on overall forum but not on just one section(forum)...please advice me how to do that??
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I need to know some code..like i want to display a ad on overall site. So, i added adcode in 'header' template.

Now, i want that this ad should not visible on a specific forum..eg. forum id=2

Please suggest some code how to do this??

I tried this code-

PHP Code:

<if condition="in_array($foruminfo[forumid], array(1,2,3))"> 


and it works fine but then it don't show ad on profiles, search page, ...etc.

I want some code like...if condition is that forum id is =xx no ad and on rest (like <else></else>) of the header ad should be visible