InputCandy makes it easier to use input in GameMaker and does all of the "settings" and "selection" for you, so you can easily import these features into other projects. It was first written by LostAstronaut.com for use with their games.
It's important to note that this is for detecting momentary actions, not for detecting textual input ("typing"). It treats mice, keyboard and gamepad input as "button states"
InputCandy has two modes:
To access Simple mode, see the script InputCandySimple included in the package. It's one function, so you don't have to import all the other stuff. It is demonstrated in rm_InputCandySimple_demo and o_InputCandySimple_demo
This asset is currently a "Work in Progress" (WIP) and is being developed at its bleeding edge here, where you can download it as a GameMaker project: https://github.com/LAGameStudio/InputCandy
This "Victorian Alcatraz" version from Github