Extract Date from file name using Regex

Question

I have the following structure for names:

GuidAsString/yyyy/MM/dd.zip

An example:

e1e2e854-e1cd-4980-83bb-2a0273f904aa/2018/11/18.zip

I would like to extract the date using regex. Regex is just not my thing.

Update: I am trying to do something like:

DateTime dateTime = DateTime.ParseExact(name, format, formatprovider)

and I am looking for the format. If you have a more elegant way that would be even better.

I would appreciate your help.

Answer 1

string input = @"e1e2e854-e1cd-4980-83bb-2a0273f904aa/2018/11/18.zip";
string pattern = @"/(\d+/\d+/\d+)";
var match = Regex.Match(input, pattern);
var date = DateTime.Parse(match.Groups[1].Value);
WriteLine(date.ToShortDateString());
// Prints: 18.11.2018

One-liner:

var date = DateTime.Parse(Regex.Match(@"e1e2e854-e1cd-4980-83bb-2a0273f904aa/2018/11/18.zip", @"/(\d+/\d+/\d+)").Groups[1].Value);

Answer 2

you could use to extract the date in string format with regex:

var st = "e1e2e854-e1cd-4980-83bb-2a0273f904aa/2018/11/18.zip";
var st1 = Regex.Match(st,@"\d{4}/\d{2}/\d{2}").Value;

st1 = "2018/11/18" if you want to convert in date format use:

var date = DateTime.Parse(st1);

Answer 3

You easily find the solution with some string manipulation. You can use String.Split method like;

var str = "e1e2e854-e1cd-4980-83bb-2a0273f904aa/2018/11/18.zip";
var year = str.Split('/')[1];
var month = str.Split('/')[2];
var day = str.Split('/')[3].Split('.')[0];

and you can parse your parts like;

var myDate = DateTime.ParseExact($"{year}{day}{month}",
                                  "yyyyddMM",
                                  CultureInfo.InvariantCulture);