If (DateTime.TryParseExact(strValueSplit.GetValue(dtFormat.Rows.IndexOf(dr)), "yyyy", CultureInfo.CreateSpecificCulture("en-US"), DateTimeStyles.None, thisYear)) Then
'something
Else
'something
End If
Dim regex As Regex = New Regex("(255[0-9])([0-1][0-2])([0-3][0-9])") '(yyyyMMdd)
Dim regex1 As Regex = New Regex("([0-1][0-2])([0-3][0-9])(255[0-9])") '(ddMMyyyy)
Dim match As Match = regex.Match("25581201")
If match.Success Then
MessageBox.Show(match.Value)
End If