Hi,
First, if you have working DoString method, this method is useless, but i'm sure it can be usefull for someone.
Credits go to PocketGnome Mac bot which use this method, and thanks to Nonowmana for give me the idea
Well ok it's really simple, the goal is to get the static address of the action bar slot that you want to use, here i will use Action Bar 1, Slot 1.
The current address of Spell Id in the action bar 1 slot 1 is : 0x011F5E70 (3.2.0) ( Then +0x4 for slot 2, etc... ).
Then just write the spell id of the spell you want to cast at the specified address, and press the right key in WoW ( action bar 1, slot 1 here ).
The best things to do with this method, is to get all your spell id in your spell book, again, it's only simple memory reading, the pointer is 0x011297E0 for the first spell id in spell book, add +0x4 for next spell id until spell id = 0.
Hope it can help someone =)