how filter source html?

[jason213123]

hi,
i building a site of ads that can accept html source for users can show their ads with images with the custum sizes and with custum fonts and tables
flash content etc
but i want block some code like php code

< php>
include "ext";
<?>

and javascript too and other code that can result in a segurity issue.
there is any function in php or other way to detect that code before save to the db?
thanks a lot for your help

[Amahdy]

-you can parse if " <?php " exists in the string or "<script" or "<?" ..etc
-you can get the value from the database as "string" and put them directly into a "string-variable" so that it won't be executed in the server side but only shown in the user side .. for the java-script , stripslashes and remove quotes (or replace by &quot; ) before displaying the string .. this won't make the script able to run but considered as a normal string ..

[jason213123]

hi,
thanks for your help i will try that