Try this:
DateTime s1= DateTime.ParseExact(Date1,"yyyyMMdd",System.Globalization.CultureInfo.InvariantCulture);
string datefin = s1.ToString("yyyy-MM-dd");
return datefin;
Try this:
DateTime s1= DateTime.ParseExact(Date1,"yyyyMMdd",System.Globalization.CultureInfo.InvariantCulture);
string datefin = s1.ToString("yyyy-MM-dd");
return datefin;