In a view if you are receiving error: False is not defined, then you probably have to transfer you variable to low string, something like:
var doAboutTab = @((ViewBag.DoAboutTab != null).ToString().ToLower());
Taken from here
In a view if you are receiving error: False is not defined, then you probably have to transfer you variable to low string, something like:
var doAboutTab = @((ViewBag.DoAboutTab != null).ToString().ToLower());
Taken from here