public void GetFilesTest() { var file = new FileEmu(); file.AddFile(@"z:\temp\aaa.txt", "", Encoding.UTF8); file.AddFile(@"z:\temp\bbb.TXT", "", Encoding.UTF8); file.AddFile(@"z:\temp\ccc.txt", "", Encoding.UTF8); file.AddFile(@"z:\temp\AAA.exe", "", Encoding.UTF8); file.AddFile(@"z:\temp\test\AAA.txt", "", Encoding.UTF8); var list = file.GetFiles(@"z:\temp", filename => { return Regex.IsMatch(filename, @"\.txt$", RegexOptions.IgnoreCase); }).ToList(); Assert.AreEqual(3, list.Count); Assert.AreEqual(@"z:\temp\aaa.txt", list[0]); Assert.AreEqual(@"z:\temp\bbb.TXT", list[1]); Assert.AreEqual(@"z:\temp\ccc.txt", list[2]); }