Override a model method via plugin I'm new to Craft and PHP, so thanks ahead of time!

Is it possible to override a model method with a plugin? For example, I want to add some additional functionality to the getUrl method of the AssetFileModel class. Can this be done in a plugin?

Thanks!
Kind of, but probably not what you're looking for.

Your plugin can certainly do a MyAssetFileModel extends AssetFileModel and (in the scope of your plugin) take advantage of existing AssetFileModel methods and properties and override them as needed.  But that's the catch... it will only be within the executing scope of your plugin.

There's no native way (without hacking core Craft files) to tell Craft "use MyAssetFileModel wherever you would normally use AssetFileModel".

However, this is certainly much more doable in the upcoming Craft 3 release since Yii 2 has native support for things like service locators and dependency injection.