Aug 27, 2018 11:33 PM|Larry Inge|LINK
I don't understand your question. You seem to be saying that if you feed an array of strings that look like treatments then you get the answer that you expect but that if you feed a file of months and numbers then you do not ??? Not really surprising.
File.ReadLines returns an enumerable where each element will be a line of the file
Skip(0) says don't skip any lines which is the same as doing nothing.
Take(1) says I only want the first line of the file. So you will return the first line of the file. The first line of the file is the name of months, the method is called GetMonths and it returns the names of months, it seems to do what you want.
What are you expecting to happen?