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TreeNode.FirstNode Property

Definition

Gets the first child tree node in the tree node collection.

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

Property Value

The first child TreeNode in the Nodes collection.

Attributes

Examples

The following code example selects the appropriate TreeNode after determining if the TreeNode passed in is selected and which TreeNode to select. This example requires that you have a Form with a TreeView control that has a TreeNodeCollection that contains several TreeNode objects. 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

Remarks

The FirstNode is the first child TreeNode in the TreeNodeCollection stored in the Nodes property of the current tree node. If the TreeNode has no child tree node, the FirstNode property returns null.

Applies to