今天有点时间，做个小例子WPF MVVM 实现TreeView 只是一个思路大家可以自由扩展

文章最后给出了源码下载地址

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模版加上了一个checkbox，选中父类的checkbox 所有的子类也相就选中。

如果子类没有全部父类的checkbox不会选中

用vmmm我们要先实现INotifyPropertyChanged

/// 
    ///     /// 
    public class NotifyPropertyBase : INotifyPropertyChanged    {        #region INotifyPropertyChanged        public void OnPropertyChanged(string propertyName)        {            if (PropertyChanged != null)            {                PropertyChanged(this, new PropertyChangedEventArgs(propertyName));            }        }        public event PropertyChangedEventHandler PropertyChanged;        #endregion    }

为了避免硬编码错误我写一个扩展方法

/// 
    /// 扩展方法    /// 避免硬编码问题    /// 
    public static class NotifyPropertyBaseEx    {        public static void SetProperty
     
      (this T tvm, Expression
      
       
        > expre) where T : NotifyPropertyBase, new()        {            string _pro = CommonFun.GetPropertyName(expre);            tvm.OnPropertyChanged(_pro);        }    }    #endregion    public class CommonFun    {        /// 
        
        /// 返回属性名        /// 
        /// 
                /// 
                /// 
                /// 
                public static string GetPropertyName
        
         (Expression
         
          
           > expr) { string _propertyName = ""; if (expr.Body is MemberExpression) { _propertyName = (expr.Body as MemberExpression).Member.Name; } else if (expr.Body is UnaryExpression) { _propertyName = ((expr.Body as UnaryExpression).Operand as MemberExpression).Member.Name; } return _propertyName; } }
          
         
        
       
      
     

下面我们就来实现treeveivew的绑定类

/// 
    /// 因为用到泛型了不能写成abstract 类    ///     /// 
    public  class MyTree : NotifyPropertyBase    {         #region 父        public MyTree Parent        {            get;            set;        }        #endregion        #region 子        public List
     
       Children        {            get;            set;        }        #endregion        #region 节点的名字        public string Name        {            get;            set;        }        #endregion        #region Constructors        public MyTree(string name)        {            this.Name=name;            this.Children=new List
      
       ();        }        public MyTree() { }        public         #endregion        #region CheckBox是否选中        bool? _isChecked;        public bool? IsChecked        {            get            {                return _isChecked;            }            set            {                SetIsChecked(value, true, true);            }        }        private void SetIsChecked(bool? value, bool checkedChildren, bool checkedParent)        {            if (_isChecked == value) return;            _isChecked = value;            //选中和取消子类            if (checkedChildren && value.HasValue && Children != null)                Children.ForEach(ch => ch.SetIsChecked(value, true, false));            //选中和取消父类            if (checkedParent && this.Parent != null)                this.Parent.CheckParentCheckState();            //通知更改                        this.SetProperty(x => x.IsChecked);        }        /// 
       
        /// 检查父类是否选 中        /// 如果父类的子类中有一个和第一个子类的状态不一样父类ischecked为null        /// 
        private void CheckParentCheckState()        {            bool? _currentState = this.IsChecked;            bool? _firstState = null;            for (int i = 0; i < this.Children.Count(); i++)            {                bool? childrenState = this.Children[i].IsChecked;                if (i == 0)                {                    _firstState = childrenState;                }                else if (_firstState != childrenState)                {                    _firstState = null;                }            }            if (_firstState != null) _currentState = _firstState;            SetIsChecked(_firstState, false, true);        }        #endregion        #region 选中的行 IsSelected        bool _isSelected;        public bool IsSelected        {            get            {                return _isSelected;            }            set            {                _isSelected = value;                this.SetProperty(x => x.IsChecked);                if (_isSelected)                {                    SelectedTreeItem = this;                    MessageBox.Show("选中的是" + SelectedTreeItem.Name);                }                else                    SelectedTreeItem = null;            }        }        #endregion        #region 选中的数据        public MyTree SelectedTreeItem        {            get;            set;        }        #endregion        #region 创建树        public void CreateTreeWithChildre( MyTree children,bool? isChecked)        {            this.Children.Add(children);            children.Parent = this;            children.IsChecked = isChecked;        }        #endregion    }
      
     

 

我们再下面实现ViewModel

public class TreeViewModel:NotifyPropertyBase    {        public List
     
       MyTrees        {            get;            set;        }        public TreeViewModel()        {            MyTrees = new List
      
       ();            MyTrees.Add(MyCreateTree());                    }        /// 
       
        /// 创建树        /// 
        /// 
               public MyTree MyCreateTree()        {            MyTree _myT = new MyTree("中国");            #region 北京            MyTree _myBJ = new MyTree("北京");            _myT.CreateTreeWithChildre(_myBJ, false);            MyTree _HD = new MyTree("海淀区");                                    MyTree _CY = new MyTree("朝阳区");            MyTree _FT = new MyTree("丰台区");            MyTree _DC = new MyTree("东城区");            _myBJ.CreateTreeWithChildre(_HD, false);            _HD.CreateTreeWithChildre(new MyTree("某某1"), false);            _HD.CreateTreeWithChildre(new MyTree("某某2"), true);            _myBJ.CreateTreeWithChildre(_CY, false);            _myBJ.CreateTreeWithChildre(_FT, false);            _myBJ.CreateTreeWithChildre(_DC, false);             #endregion            #region 河北            MyTree _myHB = new MyTree("河北");            _myT.CreateTreeWithChildre(_myHB, false);            MyTree _mySJZ = new MyTree("石家庄");            MyTree _mySD = new MyTree("山东");                     MyTree _myTS = new MyTree("唐山");            _myHB.CreateTreeWithChildre(_mySJZ, true);            _myHB.CreateTreeWithChildre(_mySD, false);            _myHB.CreateTreeWithChildre(_myTS, false);            #endregion            return _myT;        }            }
      
     

　　

我们再实现一个TreeView的模版

 

 源码地址：