C#正则表达式判断输入日期格式是否正确

/// <summary>
    /// 是否为日期型字符串
    /// </summary>
    /// <param name="StrSource">日期字符串(2008-05-08)</param>
    /// <returns></returns>
    public static bool IsDate(string StrSource)
    {
      return Regex.IsMatch(StrSource, @"^((((1[6-9]|[2-9]\d)\d{2})-(0?[13578]|1[02])-(0?[1-9]|[12]\d|3[01]))|(((1[6-9]|[2-9]\d)\d{2})-(0?[13456789]|1[012])-(0?[1-9]|[12]\d|30))|(((1[6-9]|[2-9]\d)\d{2})-0?2-(0?[1-9]|1\d|2[0-9]))|(((1[6-9]|[2-9]\d)(0[48]|[2468][048]|[13579][26])|((16|[2468][048]|[3579][26])00))-0?2-29-))$");
    }
    /// <summary>
    /// 是否为时间型字符串
    /// </summary>
    /// <param name="source">时间字符串(15:00:00)</param>
    /// <returns></returns>
    public static bool IsTime(string StrSource)
    {
      return Regex.IsMatch(StrSource, @"^((20|21|22|23|[0-1]?\d):[0-5]?\d:[0-5]?\d)$");
    }
    /// <summary>
    /// 是否为日期+时间型字符串
    /// </summary>
    /// <param name="source"></param>
    /// <returns></returns>
    public static bool IsDateTime(string StrSource)
    {
      return Regex.IsMatch(StrSource, @"^(((((1[6-9]|[2-9]\d)\d{2})-(0?[13578]|1[02])-(0?[1-9]|[12]\d|3[01]))|(((1[6-9]|[2-9]\d)\d{2})-(0?[13456789]|1[012])-(0?[1-9]|[12]\d|30))|(((1[6-9]|[2-9]\d)\d{2})-0?2-(0?[1-9]|1\d|2[0-8]))|(((1[6-9]|[2-9]\d)(0[48]|[2468][048]|[13579][26])|((16|[2468][048]|[3579][26])00))-0?2-29-)) (20|21|22|23|[0-1]?\d):[0-5]?\d:[0-5]?\d)$ ");
    }

//是否是整数
  public static bool IsInt(string StrSource)
  {
    return Regex.IsMatch(StrSource, @"^[0-9]$");
  }

  public static bool IsDate(string strDate)
  {
    if (string.IsNullOrEmpty(strDate))
      return false;
    string s_reg = @"^(?ni:(?=\\d)((?'year'((1[6-9])|([2-9]\\d))\\d\\d)(?'sep'[/.-])(?'month'0?[1-9]|1[012])\\2
(?'day'((?<!(\\2((0?[2469])|11)\\2))31)|(?<!\\2(0?2)\\2)(29|30)|((?<=((1[6-9]|[2-9]\\d)(0[48]|
[2468][048]|[13579][26])|(16|[2468][048]|[3579][26])00)\\2\\3\\2)29)|((0?[1-9])|(1\\d)|(2[0-
8])))(?:(?=\\x20\\d)\\x20|$))?((?<time>((0?[1-9]|1[012])(:[0-5]?\\d){0,2}(\\x20[AP]M))|([01]?
\\d|2[0-3])(:[0-5]?\\d){1,2}))?)$";
    Regex reg = new Regex(s_reg);
    if (reg.IsMatch(strDate.ToLower()))
       return true;
    else
       return false;
   }