TreeNode.FromHandle(TreeView, IntPtr) 方法

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

Source:

TreeNode.cs

返回具有指定句柄并分配给指定树视图控件的树节点。

public:
 static System::Windows::Forms::TreeNode ^ FromHandle(System::Windows::Forms::TreeView ^ tree, IntPtr handle);

public static System.Windows.Forms.TreeNode? FromHandle(System.Windows.Forms.TreeView tree, IntPtr handle);

static member FromHandle : System.Windows.Forms.TreeView * nativeint -> System.Windows.Forms.TreeNode

Public Shared Function FromHandle (tree As TreeView, handle As IntPtr) As TreeNode

参数

tree

TreeView

TreeView包含树节点的节点。

handle

IntPtr

nativeint

树节点的句柄。

返回

TreeNode

一个 TreeNode 表示分配给具有指定句柄的指定 TreeView 控件的树节点。

示例

下面的代码示例获取 TreeNode 已折叠并使用其属性创建它 Handle 的副本。 TreeNode原始副本已从集合TreeNodeCollection中删除，并将副本添加到集合中。 此示例要求你具有 Form 一个 TreeView 控件。 控件 TreeView 应具有两个或更多个根节点，每个节点至少有一个子节点。

private:
   void treeView1_AfterCollapse( Object^ /*sender*/, TreeViewEventArgs^ e )
   {
      // Create a copy of the e.Node from its Handle.
      TreeNode^ tn = TreeNode::FromHandle( e->Node->TreeView, e->Node->Handle );
      tn->Text = String::Concat( tn->Text, "Copy" );

      // Remove the e.Node so it can be replaced with tn.
      e->Node->Remove();

      // Add tn to the TreeNodeCollection.
      treeView1->Nodes->Add( tn );
   }

private void treeView1_AfterCollapse(object sender, TreeViewEventArgs e)
{
   // Create a copy of the e.Node from its Handle.
   TreeNode tn = TreeNode.FromHandle(e.Node.TreeView, e.Node.Handle);
   tn.Text += "Copy";
   // Remove the e.Node so it can be replaced with tn.
   e.Node.Remove();
   // Add tn to the TreeNodeCollection.
   treeView1.Nodes.Add(tn);
}

Private Sub treeView1_AfterCollapse(sender As Object, _
  e As TreeViewEventArgs) Handles treeView1.AfterCollapse
   ' Create a copy of the e.Node from its Handle.
   Dim tn As TreeNode = TreeNode.FromHandle(e.Node.TreeView, e.Node.Handle)
   tn.Text += "Copy"
   ' Remove the e.Node so it can be replaced with tn.
   e.Node.Remove()
   ' Add tn to the TreeNodeCollection.
   treeView1.Nodes.Add(tn)
End Sub

注解

将节点添加到 TreeView.Nodes 集合时，控件 TreeView 会在节点句柄可用之前发送NM_CUSTOMDRAW通知。 如果重写 WndProc 提供自定义绘图的方法 TreeView 以响应此通知，则应始终在尝试访问节点之前检查此方法 null 的返回值。

另请参阅

• TreeView
• Handle