[WTH] Someone Can Do This Script/Code

I need someone who can do this....

I'll try to explain this as simple as i can...

On my webhost I have these files.
adcode.txt
home.php
faq.php
blogpost.php
blogpost2.php
and more .php or html files....

on the adcode.txt/php/html or any file type on how you can do this... on the adcode file contains my ad codes from adsense for example...

then I want to embed the contents of the adcode file to all of my public php/html files by calling only whats inside the adcode file and not actually one by one pasting the adsense code to each file..

it's like calling only whats inside the adcode using a script/code or something and embed it to where the scirpt/code is located... its works like iFRAME but i don't want to use iframe, i want to actually embed it to the website...

This way I only need to edit whats inside the adcode file then everything will be changed and not doing it manually...

Just put your adcode in a separate php file. Then include this file anywhere in the code where you would normally paste it. Editing the adcode will result in updates for it on all pages.