static public bool ValidateParsianDate(string date)
{
    bool status = true;

    try
    {
        PersianCalendar persianCalendar = new PersianCalendar();
        CultureInfo persianCulture = new CultureInfo("fa-IR");
        DateTime persianDateTime = DateTime.ParseExact(date, "dd/MM/yyyy", persianCulture);
    }
    catch (Exception ex)
    {
        string msg = ex.Message;
        status = false;
    }

    return status;
}

static public bool ValidateParsianDate(string date)
{
    bool status = true;

    try
    {
        PersianCalendar persianCalendar = new PersianCalendar();
        var dateParts = date.Split(new char[] { '/' }).Select(d=> int.Parse(d)).ToArray();
        var date = persianCalendar.ToDateTime(dateParts[2], dateParts[1], dateParts[0], 0, 0,0,0, /*8 era of year here **/);
 }
    catch (Exception ex)
    {
        string msg = ex.Message;
        status = false;
    }

    return status;
}

public static bool IsValidDate(string date)
  {
      Regex pattern = new Regex(“^\d{4}/\d{2}/\d{2}$”);
      Regex[] arrPattern = new Regex[] {
          new Regex(“^\d{4}/\d{2}/\d{2}$”),
          new Regex(“^\d{4}/\d{2}/\d{1}$”),
          new Regex(“^\d{4}/\d{1}/\d{2}$”),
          new Regex(“^\d{4}/\d{1}/\d{1}$”),
          new Regex(“^\d{2}/\d{2}/\d{2}$”),
          new Regex(“^\d{2}/\d{2}/\d{1}$”),
          new Regex(“^\d{2}/\d{1}/\d{2}$”),
          new Regex(“^\d{2}/\d{1}/\d{1}”)
      };
      int kabise = 1387;
      int year = 0;
      int mounth = 0;
      int day = 0; bool flag = false;
      for (int i = 0; i < arrPattern.Length; i++)
      {
          if (arrPattern[i].IsMatch(date))
              flag = true;
      }
      if (flag == false) return flag;
      //جدا کننده تاریخ می تواند یکی از این کاراکترها باشد
      string[] splitDate = date.Split(‘/’,‘-’,‘:’);
      year = Convert.ToInt32(splitDate[0]);
      mounth = Convert.ToInt32(splitDate[1]);
      day = Convert.ToInt32(splitDate[2]);
      if (mounth > 12 || mounth <= 0)
          flag = false;
      else
      {
          if (mounth < 7)
          {
              if (day > 31)
              {
                  flag = false;
              }
          }
          if (mounth == 12)
          {
              int t = (year – kabise) % 4;
              if ((year – kabise) % 4 == 0)
              {
                  if (day >= 31)
                      flag = false;
              }
              else if (day >= 30)
                  flag = false;
          }
          else
          {
              if (day > 30)
                  flag = false;
          }
      }
      return flag;
  }