Create Custom Number sequence in Dynamics 365 for operations

In AX2012 or AX 2009 we directly write code on existing number sequence class​​ but in AX (7) new version need to create new class and required extend to NumberSeqApplicationModule and required delegate method for mapping.
​
1. Create EDT ChangeId.
2. Add EDT to Table ChangeLog.
3. Create new Table method numRefChangeId().
public class ChangeLog extends common
{
   static NumberSequenceReference numRefChangeId()
    {
        return NumberSeqReference::findReference(extendedTypeNum(ChangeId));
    }
}
​4. Create New Class NumberSeqModuleRisk and extend NumberSeqApplicationModule​ and a delegate method.

lass NumberSeqModuleRisk extends NumberSeqApplicationModule
{
    public void initializeReference(NumberSequenceReference _reference,
         NumberSeqDatatype _datatype, NumberSeqScope _scope)
    {
        #ISOCountryRegionCodes
        super(_reference, _datatype, _scope);

        switch (_datatype.parmDatatypeId())
        {
            case extendedTypeNum(ChangeId):
         
                if("USA")
                {
                    _reference.AllowSameAs = true;
                }
               /*if (SysCountryRegionCode::isLegalEntityInCountryRegion([#isoIT]))
               {
                   _reference.AllowSameAs = true;
               }*/
        }
    }

    protected void loadModule()
    {
        NumberSeqDatatype datatype = NumberSeqDatatype::construct();

        datatype.parmDatatypeId(extendedTypeNum(ChangeId));
        datatype.parmReferenceHelp(literalStr("Creating new ChangeId"));
        datatype.parmWizardIsManual(NoYes::No);
        datatype.parmWizardIsChangeDownAllowed(NoYes::No);
        datatype.parmWizardIsChangeUpAllowed(NoYes::No);
        datatype.parmWizardHighest(999999);
        datatype.parmSortField(1);

        datatype.addParameterType(NumberSeqParameterType::DataArea, true, false);
        this.create(datatype);     

    }

    public NumberSeqModule numberSeqModule()
    {
        return NumberSeqModule::Proj;
    }

    [SubscribesTo(classstr(NumberSeqGlobal),delegatestr(NumberSeqGlobal,buildModulesMapDelegate))]
    static void buildModulesMapSubsciber(Map numberSeqModuleNamesMap)
    {
        NumberSeqGlobal::addModuleToMap(classnum(NumberSeqModuleRisk), numberSeqModuleNamesMap);
    }
}

5. Write a job and run that
static void ChangeId(Args _args)
{
    NumberSeqModuleRisk numberSeqModuleRisk = new NumberSeqModuleRisk ();
    numberSeqModuleRisk .load();
}
6. Then run the wizard   Organization Administration -> CommonForms -> Numbersequences -> Numbersequences -> Generate -> run the wizard.

GO to Project management module -> setup -> Project management parameters form -> Num Seq

​7. Now create methods as shown on Form below.

[Form]
public class ChangeLog extends FormRun
{
    NumberSeqFormHandler numberSeqFormHandler;
    /// <summary>
    ///
    /// </summary>
    NumberSeqFormHandler numberSeqFormHandler()
    {
        if (!numberSeqFormHandler)
        {
numberSeqFormHandler=NumberSeqFormHandler::newForm(ChangeLog::numRefChangeId().NumberSequenceId,  element, ChangeLog_DS,   fieldNum(ChangeLog, ChangeId));
        }
        return numberSeqFormHandler;
    }
    public void close()
    {
        if (numberSeqFormHandler)
        {
            numberSeqFormHandler.formMethodClose();
        }
        super();
    }

    [DataSource]
    class ChangeLog
    {
        public void create(boolean _append = false,
                           boolean _extern = false)
        {
            element.numberSeqFormHandler().formMethodDataSourceCreatePre();

            super(_append);
            if (!_extern)
            {
                element.numberSeqFormHandler().formMethodDataSourceCreate(true);
            }

        public void write()
        {
            super();
            element.numberSeqFormHandler().formMethodDataSourceWrite();
        }
        public boolean validateWrite()
        {
            boolean         ret;
            ret = super();
            ret = element.numberSeqFormHandler().formMethodDataSourceValidateWrite(ret) && ret;
            if (ret)
            {
                ChangeLog.validateWrite();
            }
            return ret;
        }
        public void linkActive()
        {
            element.numberSeqFormHandler().formMethodDataSourceLinkActive();
            super();
        }

        public void delete()
        {
            element.numberSeqFormHandler().formMethodDataSourceDelete();
            super();
        }
    }
}

Now our custom number sequence is generated. Open your Form and check Num Seq by creating new record on your filed.

​ Reference: https://community.dynamics.com/ax/b/daxseed/archive/2016/11/17/ax-7-custom-number-sequence