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TreeNode.Collapse Method

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Collapses the TreeNode.

Overloads

Collapse()

Collapses the tree node.
Collapse(Boolean)

Collapses the TreeNode and optionally collapses its children.

Collapse()

Collapses the tree node.

public:
 void Collapse();
public void Collapse ();
member this.Collapse : unit -> unit
Public Sub Collapse ()

Examples

The following code example toggles the selected node when a button is clicked. If the selected node is collapsed, it is expanded, if it is expanded by calling the Expand method, it is collapsed by calling the Collapse method. This example requires that you have a Form with a TreeView control that has at least one TreeNode with at least one child TreeNode.

void button1_Click( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   if ( treeView1->SelectedNode->IsExpanded )
   {
      treeView1->SelectedNode->Collapse();
      MessageBox::Show( String::Concat( treeView1->SelectedNode->Text, " tree node collapsed." ) );
   }
   else
   {
      treeView1->SelectedNode->Expand();
      MessageBox::Show( String::Concat( treeView1->SelectedNode->Text, " tree node expanded." ) );
   }
}

private void button1_Click(object sender, System.EventArgs e)
{
   if (treeView1.SelectedNode.IsExpanded)
   {
      treeView1.SelectedNode.Collapse();
      MessageBox.Show(treeView1.SelectedNode.Text + 
        " tree node collapsed.");
   }
   else
   {
      treeView1.SelectedNode.Expand();
      MessageBox.Show(treeView1.SelectedNode.Text + 
        " tree node expanded.");
   }
}

Private Sub button1_Click(sender As Object, _
  e As System.EventArgs) Handles button1.Click
   If treeView1.SelectedNode.IsExpanded Then
      treeView1.SelectedNode.Collapse()
      MessageBox.Show(treeView1.SelectedNode.Text & _ 
        " tree node collapsed.")
   Else
      treeView1.SelectedNode.Expand()
      MessageBox.Show(treeView1.SelectedNode.Text & _
        " tree node expanded.")
   End If
End Sub

Remarks

The Collapse method collapses the current TreeNode and its child nodes. If you want to collapse only the current TreeNode, use the TreeNode.Collapse(Boolean) overload, passing true to ignore its child nodes.

Note

The state of a TreeNode is persisted. For example, if the next level of child nodes was not collapsed previously, when the Expand method is called, the child nodes appear in their previously expanded state.

See also

Applies to

Collapse(Boolean)

Collapses the TreeNode and optionally collapses its children.

public:
 void Collapse(bool ignoreChildren);
public void Collapse (bool ignoreChildren);
member this.Collapse : bool -> unit
Public Sub Collapse (ignoreChildren As Boolean)

Parameters

ignoreChildren
Boolean

true to leave the child nodes in their current state; false to collapse the child nodes.

Remarks

Use the Collapse method, passing true, when you want to collapse a node but leave its child nodes in their expanded state.

Applies to