子项发生更改时更新父项

父集合绑定到具有分层网格视图结构的radGridView。

当内部集合发生更改时，是否有任何方法可以触发父属性

父对象：

    public class CoverHierarchical : EditableModelBase<CoverHierarchical>
    {
        #region Attribute Declarations
        private Int32 m_iId;
        private string m_sName = "";
        private bool m_bIsChanged;
        private ObservableCollection<CoverContentBO> m_oCoverContent;
        #endregion
        /// <summary>
        /// Get or set the id.
        /// </summary> 
        public Int32 Id
        {
            get { return this.m_iId; }
            set
            {
                if (this.m_iId != value)
                {
                    this.IsChanged = true;
                    this.m_iId = value;
                    RaisePropertyChanged("Id");
                }
            }
        }
        /// <summary>
        /// Get or set the name.
        /// </summary> 
        public string Name
        {
            get { return this.m_sName; }
            set
            {
                if (this.m_sName != value)
                {
                    this.IsChanged = true;
                    this.m_sName = value;
                    RaisePropertyChanged("Name");
                }
            }
        }

        /// <summary>
        /// Get or set the CoverContent Collection.
        /// </summary> 
        public ObservableCollection<CoverContentBO> CoverContentCollection
        {
            get { return this.m_oCoverContent; }
            set
            {
                if (this.m_oCoverContent != value)
                {
                    this.IsChanged = true;
                    this.m_oCoverContent = value;
                    RaisePropertyChanged("CoverContentCollection");
                }
            }
        }

        /// <summary>
        /// Get or set the changed flag.
        /// </summary>
        public bool IsChanged
        {
            get { return this.m_bIsChanged || this.CoverContentCollection.Any(i=>i.IsChanged); }
            set
            {
                if (this.m_bIsChanged != value)
                {
                    this.m_bIsChanged = value;
                    RaisePropertyChanged("IsChanged");
                }
            }
        }
        #endregion
  }

和子对象

        [Serializable]
    public class CoverContentBO : EditableModelBase<CoverContentBO>
    {
        #region Attribute Declarations
        private Int32 m_iCoverId;
        private Int32 m_iId;
        private bool m_bIsChanged;

        #endregion
        #region Public Properties
        /// <summary>
        /// Get or set the cover id.
        /// </summary> 
        public Int32 CoverId
        {
            get { return this.m_iCoverId; }
            set
            {
                if (this.m_iCoverId != value)
                {
                    this.IsChanged = true;
                    this.m_iCoverId = value;
                    RaisePropertyChanged("CoverId");
                }
            }
        }
        /// <summary>
        /// Get or set the id.
        /// </summary> 
        public Int32 Id
        {
            get { return this.m_iId; }
            set
            {
                if (this.m_iId != value)
                {
                    this.IsChanged = true;
                    this.m_iId = value;
                    RaisePropertyChanged("Id");
                }
            }
        }

        /// <summary>
        /// Get or set the changed flag.
        /// </summary>
        public bool IsChanged
        {
            get { return this.m_bIsChanged; }
            set
            {
                if (this.m_bIsChanged != value)
                {
                    this.m_bIsChanged = value;
                    RaisePropertyChanged("IsChanged");
                }
            }
        }
     #endregion
   }

In-ViewModel

public ObservableCollection<CoverHierarchical> CoverHierarchicalCollection
    {
        get { return m_CoverHierarchicalCollection; }
        set
        {
            if (m_CoverHierarchicalCollection != value)
            {
                m_CoverHierarchicalCollection = value;
                OnPropertyChanged();
            }
        }
    }

CoverHierarchicalCollection已绑定到视图。如果用户编辑子网格，则子网格中会发生更改。在更改Child内部集合（CoverContentCollection）字段时，是否有任何方法可以触发父级的IsChanged属性。

    /// <summary>
    /// Get or set the CoverContent Collection.
    /// </summary> 
    public ObservableCollection<CoverContentBO> CoverContentCollection
    {
        get { return this.m_oCoverContent; }
        set
        {
            if (this.m_oCoverContent != value)
            {
                this.IsChanged = true;
                RemoveEventhandlers(m_oCoverContent);
                this.m_oCoverContent = value;
                AddEventhandlers(m_oCoverContent);
                RaisePropertyChanged("CoverContentCollection");
            }
        }
    }
    private void AddEventhandlers(ObservableCollection<CoverContentBO> oCoverContent)
    {
        foreach (var CoverContentBO in oCoverContent)
        {
            CoverContentBO.PropertyChanged +=CoverContentBO_PropertyChanged;
        }
        oCoverContent.CollectionChanged +=oCoverContent_CollectionChanged;
    }
    void oCoverContent_CollectionChanged(object sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
    {
        foreach (CoverContentBO CoverContentBO in e.OldItems)
        {
            CoverContentBO.PropertyChanged -=CoverContentBO_PropertyChanged;
        }
        foreach (CoverContentBO CoverContentBO in e.NewItems)
        {
            CoverContentBO.PropertyChanged +=CoverContentBO_PropertyChanged;
        }
    }
    void CoverContentBO_PropertyChanged(object sender, PropertyChangedEventArgs e)
    {
        if (e.PropertyName == "IsChanged")
        {
            IsChanged = true;
        }
    }
    private void RemoveEventhandlers(ObservableCollection<CoverContentBO> oCoverContent)
    {
        foreach (var CoverContentBO in oCoverContent)
        {
            CoverContentBO.PropertyChanged -=CoverContentBO_PropertyChanged;
        }
        oCoverContent.CollectionChanged -=oCoverContent_CollectionChanged;
    }