I want to override
Mage_Adminhtml_Controller_Action in my module
I've searched the net,but I couldn't find anyway to do this. Is it like the controllers, or it has a different way?
I appreciate any help.
You cannot override that controller.
Well...actually you can but it will have no effect.
Mage_Adminhtml_Controller_Action class is never instantiated. It is there as a common parent class for the rest of the admin controllers.
even if you find a way to rewrite it all the other admin controllers will extend the original class so your modification will be useless.
If you want to change something in it you have to copy it to
app/code/local/Mage/Adminhtml/Controller/Action.php and make your modifications there.
Here are more details about why you cannot rewrite some classes in Magento