app_code folder containing base.cs, which is intented to pass on its class page_load

hi,
i do have an app_code folder, which contains a base.cs, which is intented to have its class page_load to override other .aspx-files (without masterpage.master) when the page_load-class of these files is loaded. i wrote the class in base.cs as "public override page_load", but this gives an error when compiling.
what am i doing wrong?
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