Directory.GetFiles get multiple files using filePattern

Question

How do I setup pattern to return multiple files, but only such that I am looking for.

I have a directory which contains files:

marks v1.csv,
marks_east.csv
marks.csv
marks_west.csv
marks23.csv
marks24.csv

I need marks.csv, marks_east.csv, marks_west.csv using filePattern .

Earlier I was using exact file name as I was interested in only one file. Now I want to reuse same process by modifying filePattern .

var files = Directory.GetFiles(sourceDirectory, filePattern).OrderBy(d => new FileInfo(d).CreationTime);

Answer 1

Directory.GetFiles supports wildcards.

var files = Directory.GetFiles(sourceDirectory, "marks_*.csv").OrderBy(d => new FileInfo(d).CreationTime);

This will not catch marks.csv though. Regex would be very well suited for this, but alas the GetFiles function does not support regular expressions. A quick (a bit hacky) solution might be:

var files = Directory.GetFiles(sourceDirectory, "marks_*.csv");
if (File.Exists(sourceDirectory+"marks.csv"))
    files.Insert(0, "marks.csv");
files.OrderBy(d => new FileInfo(d).CreationTime);