How to check a Persian date between two Persian dates?

My Persian date format can take one of these formats: mm/YYYY or YYYY/mm There is no day information, just year and month. I want to check a Persian date between two Persian dates: For example, 1400/01 is between 1399/07 and 1400/03 How can I do this while day information is not available?


 public static DateTime GetDate(string initialValue)
        int pos = initialValue.IndexOf("/");
        string dformat = pos == 2 ? "MM/yyyy" : "yyyy/MM";
        DateTime dDate = DateTime.MinValue;
        DateTime.TryParseExact(initialValue, dformat, CultureInfo.GetCultureInfo("fa-IR"), DateTimeStyles.None, out dDate);
        return dDate;
    static void Main(string[] args)
        string one = "1399/07";
        string two = "03/1400";
        string three = "01/1400";
        DateTime dOne = GetDate(one);
        DateTime dTwo = GetDate(two);
        DateTime dThree = GetDate(three);
        bool answer = dThree >= dOne && dThree <= dTwo;
        Console.WriteLine($"'{dThree.ToString("yyyy-MM-dd")}' is between '{dOne.ToString("yyyy-MM-dd")}' and '{dTwo.ToString("yyyy-MM-dd")}'? => {answer}");