IAssign field implementation

IAssignInterface.cs

        #region OwnerID
        public abstract class ownerID : BqlGuid.Field<ownerID>
        {
        }
        [PXDBGuid]
        [PXDefault(typeof(ownerID), PersistingCheck = PXPersistingCheck.Nothing)]
        [PXOwnerSelector]
        [PXUIField(DisplayName = "Owner")]
        public virtual Guid? OwnerID { get; set; }
        #endregion

        #region WorkgroupID
        public abstract class workgroupID : BqlInt.Field<workgroupID>
        {
        }
        [PXDBInt]
        [PXDefault(typeof(workgroupID), PersistingCheck = PXPersistingCheck.Nothing)]
        [PXCompanyTreeSelector]
        [PXUIField(DisplayName = "Workgroup", Enabled = false)]
        public virtual int? WorkgroupID { get; set; }
        #endregion