highly suggest using notepad++ over notepad....
https://notepad-plus-plus.org/download/v6.9.2.html
you can set the language as c# and it will highlight the various elements which makes it easier to read, as well as close (fold up) the functions, as well as gives you line numbers, multiple tabs, can compare files side by side etc etc
I have a gcode plugin too which makes that very readable.
Rob