Convert All Hirji Formats into Gregorian

//Amer Atiyah, http://blog.amer-ax.com
static date hijri2GrDate(DAPHijridateStr   hijriDateStr)
{
    System.Globalization.CultureInfo arCul = new System.Globalization.CultureInfo("ar-SA");
    System.Globalization.CultureInfo enCul = new System.Globalization.CultureInfo("en-US");
    System.DateTime                  tempDateTime;
    str                              strTemp;
    System.String[]                  arr;
    date                             grDate;
;
 
    //all expected dates formats
    arr = new System.String[18]();
    arr.SetValue("dd M yyyy",  0);
    arr.SetValue("yyyy/MM/dd",  1);
    arr.SetValue("yyyy/M/d",    2);
    arr.SetValue("d/M/yyyy",    3);
    arr.SetValue("dd/MM/yyyy",  4);
    arr.SetValue("yyyy-MM-dd",  5);
    arr.SetValue("d/MM/yyyy",   6);
    arr.SetValue("dd/M/yyyy",   7);
    arr.SetValue("yyyy-M-d",    8);
    arr.SetValue("dd-MM-yyyy",  9);
    arr.SetValue("yyyy MM dd",  10);
    arr.SetValue("d-M-yyyy",    11);
    arr.SetValue("d-MM-yyyy",   12);
    arr.SetValue("dd-M-yyyy",   13);
    arr.SetValue("d M yyyy",    14);
    arr.SetValue("dd MM yyyy",  15);
    arr.SetValue("yyyy M d",    16);
    arr.SetValue("d MM yyyy",   17);
 
    try
    {
        tempDateTime = System.DateTime::ParseExact(hijriDateStr, arr, arCul, System.Globalization.DateTimeStyles::AllowWhiteSpaces);
    }
    catch
    {
        error("Unexpected Hirji date format.");
        return datenull();
    }
    strTemp = tempDateTime.ToString("dd/MM/yyyy");
    grDate = str2date(strTemp, 123);
 
    return grDate;
}