WCF错误“循环引用”

Question

我首先使用EF6.1.3代码和WCF 使用包含功能时，获取错误“循环引用”

  using (var db = new AvanEntites())
            {
               db.Configuration.ProxyCreationEnabled = false;
               db.Configuration.LazyLoadingEnabled = false;

                data = db.WorkflowPositions.Include("RolePermissions").Include("RolePermissions.Application").AsNoTracking.ToArray();
            }

我的课程：

  public class BaseModel : INotifyPropertyChanged
    {
        private bool _isActive;
        private DateTime? _lastUpdateTime;
        private DateTime? _creationDate;
        private long? _lastUpdatedBy;
        private long? _createdBy;

        public long? CreatedBy
        {
            get { return _createdBy; }
            set
            {
                if (value == _createdBy) return;
                _createdBy = value;
                OnPropertyChanged(nameof(CreatedBy));
            }
        }

        public long? LastUpdatedBy
        {
            get { return _lastUpdatedBy; }
            set
            {
                if (value == _lastUpdatedBy) return;
                _lastUpdatedBy = value;
                OnPropertyChanged(nameof(LastUpdatedBy));
            }
        }

        public DateTime? CreationDate
        {
            get { return _creationDate; }
            set
            {
                if (value.Equals(_creationDate)) return;
                _creationDate = value;
                OnPropertyChanged(nameof(CreationDate));
            }
        }

        public DateTime? LastUpdateTime
        {
            get { return _lastUpdateTime; }
            set
            {
                if (value.Equals(_lastUpdateTime)) return;
                _lastUpdateTime = value;
                OnPropertyChanged(nameof(LastUpdateTime));
            }
        }

        public bool IsActive
        {
            get { return _isActive; }
            set
            {
                if (value == _isActive) return;
                _isActive = value;
                OnPropertyChanged(nameof(IsActive));
            }
        }

        public event PropertyChangedEventHandler PropertyChanged;

        [NotifyPropertyChangedInvocator]
        protected virtual void OnPropertyChanged(string propertyName)
        {
            PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
        }
    }
         public partial class WorkflowPosition:BaseModel
            {
                private ObservableCollection<WorkflowContractPosition> _workflowContractPositions;
                private string _namePosition;
                private long _id;
                private ObservableCollection<RolePermission> _rolePermissions;
                // [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2214:DoNotCallOverridableMethodsInConstructors")]
                public WorkflowPosition()
                {
                    WorkflowContractPositions = new ObservableCollection<WorkflowContractPosition>();
                }

                public long Id
                {
                    get { return _id; }
                    set
                    {
                        if (value == _id) return;
                        _id = value;
                        OnPropertyChanged(nameof(Id));
                    }
                }

                public string NamePosition
                {
                    get { return _namePosition; }
                    set
                    {
                        if (value == _namePosition) return;
                        _namePosition = value;
                        OnPropertyChanged(nameof(NamePosition));
                    }
                }
                // [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Usage", "CA2227:CollectionPropertiesShouldBeReadOnly")]
                public virtual ObservableCollection<WorkflowContractPosition> WorkflowContractPositions
                {
                    get { return _workflowContractPositions; }
                    set
                    {
                        if (Equals(value, _workflowContractPositions)) return;
                        _workflowContractPositions = value;
                        OnPropertyChanged(nameof(WorkflowContractPositions));
                    }
                }
                public virtual ObservableCollection<RolePermission> RolePermissions
                {
                    get
                    {
                        return _rolePermissions;
                    }
                    set
                    {
                        if (Equals(value, _rolePermissions)) return;
                        _rolePermissions = value;
                        OnPropertyChanged(nameof(RolePermissions));
                    }
                }
            }


     public class RolePermission:BaseModel
        {
            private WorkflowPosition _workflowPosition;
            private Application _application;
            private long _applicationId;
            private long _positionId;
            private long _permissionId;

            public RolePermission()
            {

            }
            [Key]
            public long PermissionId
            {
                get { return _permissionId; }
                set
                {
                    if (value == _permissionId) return;
                    _permissionId = value;
                    OnPropertyChanged(nameof(PermissionId));
                }
            }
            public long PositionId
            {
                get { return _positionId; }
                set
                {
                    if (value == _positionId) return;
                    _positionId = value;
                    OnPropertyChanged(nameof(PositionId));
                }
            }
            public long ApplicationId
            {
                get { return _applicationId; }
                set
                {
                    if (value == _applicationId) return;
                    _applicationId = value;
                    OnPropertyChanged(nameof(ApplicationId));
                }
            }
            public virtual Application Application
            {
                get { return _application; }
                set
                {
                    if (Equals(value, _application)) return;
                    _application = value;
                    OnPropertyChanged(nameof(Application));
                }
            }
            public virtual WorkflowPosition WorkflowPosition
            {
                get { return _workflowPosition; }
                set
                {
                    if (Equals(value, _workflowPosition)) return;
                    _workflowPosition = value;
                    OnPropertyChanged(nameof(WorkflowPosition));
                }
            }
        }


     public class Application : BaseModel
        {
            private ObservableCollection<RolePermission> _rolePermissions;
            private string _applicationName;
            private long _applicationId;
            private string _madule;
            public Application() { }

            [Key]
            public long ApplicationId
            {
                get { return _applicationId; }
                set
                {
                    if (value == _applicationId) return;
                    _applicationId = value;
                    OnPropertyChanged(nameof(ApplicationId));
                }
            }
            public string ApplicationName
            {
                get { return _applicationName; }
                set
                {
                    if (value == _applicationName) return;
                    _applicationName = value;
                    OnPropertyChanged(nameof(ApplicationName));
                }
            }
            public string Madule
            {
                get { return _madule; }
                set
                {
                    if (value == _madule) return;
                    _madule = value;
                    OnPropertyChanged(nameof(Madule));
                }
            }
            public virtual ObservableCollection<RolePermission> RolePermissions
            {
                get { return _rolePermissions; }
                set
                {
                    if (Equals(value, _rolePermissions)) return;
                    _rolePermissions = value;
                    OnPropertyChanged(nameof(RolePermissions));
                }
            }
        }