TreeNode.FirstNode Propiedad

Definición

Obtiene el primer nodo de árbol secundario en la colección de nodos de árbol.Gets the first child tree node in the tree node collection.

public:
 property System::Windows::Forms::TreeNode ^ FirstNode { System::Windows::Forms::TreeNode ^ get(); };
[System.ComponentModel.Browsable(false)]
public System.Windows.Forms.TreeNode FirstNode { get; }
member this.FirstNode : System.Windows.Forms.TreeNode
Public ReadOnly Property FirstNode As TreeNode

Valor de propiedad

Primer TreeNode secundario de la colección de Nodes.The first child TreeNode in the Nodes collection.

Atributos

Ejemplos

En el ejemplo de código siguiente se TreeNode selecciona el adecuado después TreeNode de determinar si el que se TreeNode ha pasado está seleccionado y cuál se va a seleccionar.The following code example selects the appropriate TreeNode after determining if the TreeNode passed in is selected and which TreeNode to select. Este ejemplo requiere Form que tenga un con un TreeView control que tenga un TreeNodeCollection que contiene varios TreeNode objetos.This example requires that you have a Form with a TreeView control that has a TreeNodeCollection that contains several TreeNode objects. También requiere que tenga un ComboBox con los siguientes elementos: "PREVIOUS", "PreviousVisible", "Next", "NextVisible", "First" y "Last".It also requires that you have a ComboBox with the following items: "Previous", "PreviousVisible", "Next", "NextVisible", "First", and "Last".

void SelectNode( TreeNode^ node )
{
   if ( node->IsSelected )
   {
      
      // Determine which TreeNode to select.
      String^ str = myComboBox->Text;
      if ( str->Equals( "Previous" ) )
               node->TreeView->SelectedNode = node->PrevNode;
      else
      if ( str->Equals( "PreviousVisible" ) )
               node->TreeView->SelectedNode = node->PrevVisibleNode;
      else
      if ( str->Equals( "Next" ) )
               node->TreeView->SelectedNode = node->NextNode;
      else
      if ( str->Equals( "NextVisible" ) )
               node->TreeView->SelectedNode = node->NextVisibleNode;
      else
      if ( str->Equals( "First" ) )
               node->TreeView->SelectedNode = node->FirstNode;
      else
      if ( str->Equals( "Last" ) )
               node->TreeView->SelectedNode = node->LastNode;
   }

   node->TreeView->Focus();
}
private void SelectNode(TreeNode node)
{
    if(node.IsSelected)
    {
        // Determine which TreeNode to select.
        switch(myComboBox.Text)
        {
            case "Previous":
                node.TreeView.SelectedNode = node.PrevNode;
                break;
            case "PreviousVisible":
                node.TreeView.SelectedNode = node.PrevVisibleNode;
                break;
            case "Next":
                node.TreeView.SelectedNode = node.NextNode;
                break;
            case "NextVisible":
                node.TreeView.SelectedNode = node.NextVisibleNode;
                break;
            case "First":
                node.TreeView.SelectedNode = node.FirstNode;
                break;
            case "Last":
                node.TreeView.SelectedNode = node.LastNode;
                break;
        }
    }
    node.TreeView.Focus();
}
Private Sub SelectNode(node As TreeNode)
   If node.IsSelected Then
      ' Determine which TreeNode to select.
      Select Case myComboBox.Text
         Case "Previous"
            node.TreeView.SelectedNode = node.PrevNode
         Case "PreviousVisible"
            node.TreeView.SelectedNode = node.PrevVisibleNode
         Case "Next"
            node.TreeView.SelectedNode = node.NextNode
         Case "NextVisible"
            node.TreeView.SelectedNode = node.NextVisibleNode
         Case "First"
            node.TreeView.SelectedNode = node.FirstNode
         Case "Last"
            node.TreeView.SelectedNode = node.LastNode
      End Select
   End If
   node.TreeView.Focus()
End Sub

Comentarios

Es el primer elemento secundario TreeNode TreeNodeCollection del almacenado en la Nodes propiedad del nodo de árbol actual. FirstNodeThe FirstNode is the first child TreeNode in the TreeNodeCollection stored in the Nodes property of the current tree node. Si el TreeNode no tiene ningún nodo de árbol secundario FirstNode , la nullpropiedad devuelve.If the TreeNode has no child tree node, the FirstNode property returns null.

Se aplica a