Conversions from UTCdate time to string and vice versa.

static void datetime2str()
{
 str resultstr;
utcDateTime result;
resultstr   =  DateTimeUtil::toFormattedStr(result,321, DateDay::Digits2, DateSeparator::Hyphen, DateMonth::Digits2, DateSeparator::Hyphen, DateYear::Digits4, TimeSeparator::Colon, TimeSeparator::Colon, DateFlags::None);
info(resultstr);
}
The function date2str  take following parameters :
1- the date .
2- the date style dmy or ymd or....etc .
3- number of digits for day .
4- separator
5- number of digits for month.
6- separator 
7- number of digits for year. 
================================================================
static void string2datetime()
{
     System.Globalization.CultureInfo culture
    = System.Globalization.CultureInfo::get_InvariantCulture();
    str resultstr;
   utcDateTime result;
   try
    {
     
         result= System.DateTime::ParseExact(
                             "2007-05-28 X 23:59:04",
                            "yyyy-MM-dd X HH:mm:ss",
                            culture);
     
         info(strFmt("%1",result));
    }
    catch (Exception::CLRError)
    {
        throw error(AifUtil::getClrErrorMessage());
    }
}
https://community.dynamics.com/ax/f/33/t/125802
============================================================

https://msdn.microsoft.com/en-us/library/cc553823.aspx

static void JobDateTimeGlobalMarshal(Args _args)
{
    System.DateTime netDttm;
    utcdatetime xppDttm;
    str xppString;
    ;
    xppDttm = 2007-06-05T23:22:21; // ISO standard format.
    
    // Convert X++ to .NET.
    netDttm = Global::utcDateTime2SystemDateTime(xppDttm);
    
    // Convert .NET to X++.
    xppDttm = Global::CLRSystemDateTime2UtcDateTime(netDttm);
    
    xppString = DateTimeUtil::toStr(xppDttm);
    info("xppDttm: " + xppString);
}

===========================================================================

static void FormatUtcdatetime(Args _args)
{
    
     System.Globalization.CultureInfo culture
    = System.Globalization.CultureInfo::get_InvariantCulture();
    str resultstr,frstpart,secondpart;
    utcDateTime result;
    result =    DateTimeUtil::getSystemDateTime();
     //info(strFmt("%1",result));
    resultstr   =  DateTimeUtil::toFormattedStr(result,321, DateDay::Digits2, DateSeparator::Hyphen, DateMonth::Digits2, DateSeparator::Hyphen, DateYear::Digits4, TimeSeparator::Colon, TimeSeparator::Colon, DateFlags::None);
    frstpart    = subStr(resultstr,0,10);
    secondpart    = subStr(resultstr,11,9);
    resultstr   =   frstpart+"T"+"09:20:06";//+"09:16:30";
     result = DateTimeUtil::parse(frstpart+"T"+"09:20:06");
     
    //info(secondpart);
    // info(frstpart+"T"+secondpart);
    try
    {
        /* result= System.DateTime::ParseExact(
                            "2007-05-28T23:59:04",
                            "yyyy'-'MM'-'dd'T'HH':'mm':'ss",
                            culture);*/
  result= System.DateTime::ParseExact(
                             "2007-05-28 X 23:59:04",
                            "yyyy-MM-dd X HH:mm:ss",
                            culture);
    //result  =   DateTimeUtil::parse(resultstr);
    info(strFmt("%1",result));
    }
    catch (Exception::CLRError)
    {
        throw error(AifUtil::getClrErrorMessage());
    }
    //yyyy'-'MM'-'dd'T'HH':'mm':'ss
}

https://msdn.microsoft.com/en-us/library/system.globalization.datetimeformatinfo.sortabledatetimepattern(v=vs.100).aspx

https://msdn.microsoft.com/en-us/library/system.datetime.parseexact(v=vs.110).aspx