c# search last key word .log file

Question

I am trying to search through a text /.log file for the key word "DEBUG 2018-06-04T13:27:15+00:00" Once the last key word DEBUG is found, I would then like to compare the date and time to current date $ time and if older than 10 minutes output fail.

file.ReadAllLines and StreamReader, but struggling to figure out how to read the last instance of the key word and compare the time. — Ettienne, Jun 09 '18 at 19:41
You should also provide some specifications on the logic used to compare the `DateTime` values. — Jimi, Jun 09 '18 at 19:43
You will have hard times here if you post questions where you just requires someone to write code for you. I suggest to read [ask] before posting nexttime — Steve, Jun 09 '18 at 19:43
Thank you everyone for all the help. I will be sure to read through the How to Ask page again. — Ettienne, Jun 10 '18 at 19:11

jspcal · Accepted Answer · 2018-06-09T20:19:40.200

You can extract all the matching substrings with Regex.Matches:

String text = File.ReadAllText(@"C:\My\File\Path.txt");

MatchCollection matches = Regex.Matches(
    text,
    @"DEBUG (\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\+\d{2}:\d{2})"
)

Inspect the last match:

if (matches.Count > 0) {
    Match last = matches[matches.Count - 1];
    DateTime dt = DateTime.Parse(last.Groups[1].Value);

    if (DateTime.Now > dt.AddMinutes(10)) {
         Console.WriteLine("Last date entry is older than 10 minutes ago: {0}", dt);
    }
}

Or loop through all matches:

foreach (Match match in matches) {
    // Parse the date string in the matched text:
    DateTime dt = DateTime.Parse(match.Groups[1].Value);

    if (DateTime.Now > dt.AddMinutes(10)) {
        // Date is older than 10 minutes ago
        Console.WriteLine("Date is older than 10 minutes ago: {0}", dt);
    }
}

c# search last key word .log file

1 Answers1