Question

How can I remove a whole line from a text file if the first word matches to a variable I have?

What I’m currently trying is:

List<string> lineList = File.ReadAllLines(dir + "textFile.txt").ToList();
lineList = lineList.Where(x => x.IndexOf(user) <= 0).ToList();
File.WriteAllLines(dir + "textFile.txt", lineList.ToArray());

But I can’t get it to remove.

Answer 1

The only mistake that you have is you are checking <= 0 with indexOf, instead of = 0.

-1 is returned when the string does not contain the searched for string.

<= 0 means either starts with or does not contain

=0 means starts with <- This is what you want