TreeNode 类

定义

public ref class TreeNode : MarshalByRefObject, ICloneable, System::Runtime::Serialization::ISerializable

[System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.TreeNodeConverter))]
[System.Serializable]
public class TreeNode : MarshalByRefObject, ICloneable, System.Runtime.Serialization.ISerializable

[<System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.TreeNodeConverter))>]
[<System.Serializable>]
type TreeNode = class
    inherit MarshalByRefObject
    interface ICloneable
    interface ISerializable

Public Class TreeNode
Inherits MarshalByRefObject
Implements ICloneable, ISerializable

继承

Object

MarshalByRefObject

TreeNode

派生

System.ComponentModel.Design.ObjectSelectorEditor.SelectorNode

System.Workflow.ComponentModel.Design.WorkflowOutlineNode

属性

TypeConverterAttribute SerializableAttribute

实现

ICloneable ISerializable

示例

下面的代码示例在 控件中 TreeView 显示客户信息。 根树节点显示客户名称，子树节点显示分配给每个客户的订单号。 在此示例中，将显示 1，000 个客户，每个客户有 15 个订单。 使用 和 方法取消重绘TreeView，并在 创建和绘制TreeNode对象时TreeView显示等待Cursor。EndUpdateBeginUpdate 此示例要求你有一个 Customer 可以保存 对象集合的 Order 对象。 它还要求已在 上Form创建了 控件的TreeView实例。

// The basic Customer class.
ref class Customer: public System::Object
{
private:
   String^ custName;

protected:
   ArrayList^ custOrders;

public:
   Customer( String^ customername )
   {
      custName = "";
      custOrders = gcnew ArrayList;
      this->custName = customername;
   }


   property String^ CustomerName 
   {
      String^ get()
      {
         return this->custName;
      }

      void set( String^ value )
      {
         this->custName = value;
      }

   }

   property ArrayList^ CustomerOrders 
   {
      ArrayList^ get()
      {
         return this->custOrders;
      }

   }

};


// End Customer class
// The basic customer Order class.
ref class Order: public System::Object
{
private:
   String^ ordID;

public:
   Order( String^ orderid )
   {
      ordID = "";
      this->ordID = orderid;
   }


   property String^ OrderID 
   {
      String^ get()
      {
         return this->ordID;
      }

      void set( String^ value )
      {
         this->ordID = value;
      }

   }

};
// End Order class



void FillMyTreeView()
{
   // Add customers to the ArrayList of Customer objects.
   for ( int x = 0; x < 1000; x++ )
   {
      customerArray->Add( gcnew Customer( "Customer " + x ) );
   }
   
   // Add orders to each Customer object in the ArrayList.
   IEnumerator^ myEnum = customerArray->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Customer^ customer1 = safe_cast<Customer^>(myEnum->Current);
      for ( int y = 0; y < 15; y++ )
      {
         customer1->CustomerOrders->Add( gcnew Order( "Order " + y ) );
      }
   }

   // Display a wait cursor while the TreeNodes are being created.
   ::Cursor::Current = gcnew System::Windows::Forms::Cursor( "MyWait.cur" );
   
   // Suppress repainting the TreeView until all the objects have been created.
   treeView1->BeginUpdate();
   
   // Clear the TreeView each time the method is called.
   treeView1->Nodes->Clear();
   
   // Add a root TreeNode for each Customer object in the ArrayList.
   myEnum = customerArray->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Customer^ customer2 = safe_cast<Customer^>(myEnum->Current);
      treeView1->Nodes->Add( gcnew TreeNode( customer2->CustomerName ) );
      
      // Add a child treenode for each Order object in the current Customer object.
      IEnumerator^ myEnum = customer2->CustomerOrders->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         Order^ order1 = safe_cast<Order^>(myEnum->Current);
         treeView1->Nodes[ customerArray->IndexOf( customer2 ) ]->Nodes->Add( gcnew TreeNode( customer2->CustomerName + "." + order1->OrderID ) );
      }
   }
   
   // Reset the cursor to the default for all controls.
   ::Cursor::Current = Cursors::Default;
   
   // Begin repainting the TreeView.
   treeView1->EndUpdate();
}

// The basic Customer class.
public class Customer : System.Object
{
   private string custName = "";
   protected ArrayList custOrders = new ArrayList();

   public Customer(string customername)
   {
      this.custName = customername;
   }

   public string CustomerName
   {      
      get{return this.custName;}
      set{this.custName = value;}
   }

   public ArrayList CustomerOrders 
   {
      get{return this.custOrders;}
   }
} // End Customer class 

// The basic customer Order class.
public class Order : System.Object
{
   private string ordID = "";

   public Order(string orderid)
   {
      this.ordID = orderid;
   }

   public string OrderID
   {      
      get{return this.ordID;}
      set{this.ordID = value;}
   }
} // End Order class

// Create a new ArrayList to hold the Customer objects.
private ArrayList customerArray = new ArrayList(); 

private void FillMyTreeView()
{
   // Add customers to the ArrayList of Customer objects.
   for(int x=0; x<1000; x++)
   {
      customerArray.Add(new Customer("Customer" + x.ToString()));
   }

   // Add orders to each Customer object in the ArrayList.
   foreach(Customer customer1 in customerArray)
   {
      for(int y=0; y<15; y++)
      {
         customer1.CustomerOrders.Add(new Order("Order" + y.ToString()));    
      }
   }

   // Display a wait cursor while the TreeNodes are being created.
   Cursor.Current = new Cursor("MyWait.cur");
        
   // Suppress repainting the TreeView until all the objects have been created.
   treeView1.BeginUpdate();

   // Clear the TreeView each time the method is called.
   treeView1.Nodes.Clear();

   // Add a root TreeNode for each Customer object in the ArrayList.
   foreach(Customer customer2 in customerArray)
   {
      treeView1.Nodes.Add(new TreeNode(customer2.CustomerName));
          
      // Add a child treenode for each Order object in the current Customer object.
      foreach(Order order1 in customer2.CustomerOrders)
      {
         treeView1.Nodes[customerArray.IndexOf(customer2)].Nodes.Add(
           new TreeNode(customer2.CustomerName + "." + order1.OrderID));
      }
   }

   // Reset the cursor to the default for all controls.
   Cursor.Current = Cursors.Default;

   // Begin repainting the TreeView.
   treeView1.EndUpdate();
}

Public Class Customer
   Inherits [Object]
   Private custName As String = ""
   Friend custOrders As New ArrayList()

   Public Sub New(ByVal customername As String)
      Me.custName = customername
   End Sub

   Public Property CustomerName() As String
      Get
         Return Me.custName
      End Get
      Set(ByVal Value As String)
         Me.custName = Value
      End Set
   End Property

   Public ReadOnly Property CustomerOrders() As ArrayList
      Get
         Return Me.custOrders
      End Get
   End Property
End Class


Public Class Order
   Inherits [Object]
   Private ordID As String

   Public Sub New(ByVal orderid As String)
      Me.ordID = orderid
   End Sub

   Public Property OrderID() As String
      Get
         Return Me.ordID
      End Get
      Set(ByVal Value As String)
         Me.ordID = Value
      End Set
   End Property
End Class

' Create a new ArrayList to hold the Customer objects.
Private customerArray As New ArrayList()

Private Sub FillMyTreeView()
   ' Add customers to the ArrayList of Customer objects.
   Dim x As Integer
   For x = 0 To 999
      customerArray.Add(New Customer("Customer" + x.ToString()))
   Next x

   ' Add orders to each Customer object in the ArrayList.
   Dim customer1 As Customer
   For Each customer1 In customerArray
      Dim y As Integer
      For y = 0 To 14
         customer1.CustomerOrders.Add(New Order("Order" + y.ToString()))
      Next y
   Next customer1

   ' Display a wait cursor while the TreeNodes are being created.
   Cursor.Current = New Cursor("MyWait.cur")

   ' Suppress repainting the TreeView until all the objects have been created.
   treeView1.BeginUpdate()

   ' Clear the TreeView each time the method is called.
   treeView1.Nodes.Clear()

   ' Add a root TreeNode for each Customer object in the ArrayList.
   Dim customer2 As Customer
   For Each customer2 In customerArray
      treeView1.Nodes.Add(New TreeNode(customer2.CustomerName))

      ' Add a child TreeNode for each Order object in the current Customer object.
      Dim order1 As Order
      For Each order1 In customer2.CustomerOrders
         treeView1.Nodes(customerArray.IndexOf(customer2)).Nodes.Add( _
    New TreeNode(customer2.CustomerName + "." + order1.OrderID))
      Next order1
   Next customer2

   ' Reset the cursor to the default for all controls.
   Cursor.Current = System.Windows.Forms.Cursors.Default

   ' Begin repainting the TreeView.
   treeView1.EndUpdate()
End Sub

注解

集合Nodes包含分配给当前 TreeNode的所有子TreeNode对象。 可以添加、删除或克隆 TreeNode;执行此操作时，将添加、删除或克隆所有子树节点。 每个都可以 TreeNode 包含其他 TreeNode 对象的集合。 这会使在循环访问集合时很难确定你在 TreeView 中的位置。 若要确定树结构中的位置，请使用 FullPath 属性。 FullPath可以使用字符串值分析字符串，PathSeparator以确定标签的开始和结束位置TreeNode。

通过 TreeNode 显式设置 属性来 Text 设置标签。 替代方法是使用具有表示Text属性的字符串参数的构造函数之TreeNode一创建树节点。 标签显示在图像旁边 TreeNode （如果显示）。

若要在树节点旁边显示图像，请将 分配给ImageList父控件的 属性，并通过在 属性中ImageList引用其索引值来分配 Image 。TreeViewImageList 将 ImageIndex 属性设置为在 处于未选中状态时TreeNode要显示的 的索引值Image。 同样，将 SelectedImageIndex 属性设置为在选择 时TreeNode要显示的 的索引值Image。

可以通过使用以下属性值选择特定的树节点并循环访问Nodes集合：FirstNode、、LastNode、NextNode、PrevNodeNextVisibleNode、 PrevVisibleNode。 TreeNode将上述属性之一返回的 分配给 属性，TreeView.SelectedNode以在 控件中选择TreeView该树节点。

树节点可以展开以显示下一级别的子树节点。 用户可以通过TreeNode按 旁边的TreeNode加号 (+) 按钮（如果显示）来展开 ，也可以通过调用 Expand 方法展开 TreeNode 。 若要展开集合中的所有 Nodes 子树节点级别，请 ExpandAll 调用 方法。 可以通过调用 Collapse 方法折叠子TreeNode级别，或者用户可以按 旁边的减 () 按钮TreeNode（如果显示）。 还可以调用 方法， Toggle 在展开状态和折叠状态之间交替 TreeNode 。

树节点可以选择显示复选框。 若要显示复选框，请将 的 属性设置为 CheckBoxestrue。TreeView 对于处于选中状态的树节点，属性 Checked 设置为 true 。

构造函数

属性

方法

显式接口实现

适用于

另请参阅

• TreeView
• TreeNodeCollection
• 如何：添加和删除 Windows 窗体 TreeView 控件中的节点