TreeNode.Expand Method ()

 
System_CAPS_noteNote

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Expands the tree node.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public void Expand()

The Expand method expands the current TreeNode down to the next level of nodes.

System_CAPS_noteNote

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.

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.

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.");
   }
}

.NET Framework
Available since 1.1
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