//=====================================================================
/// <summary>
/// This method can be used to enumerate tree nodes in a more convenient way using a <c>foreach</c>
/// loop without having to manually construct and manage the enumerator.
/// </summary>
/// <param name="start">The node at which to start enumeration.</param>
/// <param name="enumerateSiblings">True to enumerate the starting node's siblings as well or false to
/// stop after enumerating the starting node and all of its children.</param>
/// <returns>An enumerable list of tree nodes</returns>
public static IEnumerable <TreeNode> Enumerate(TreeNode start, bool enumerateSiblings)
{
var tne = new TreeNodeEnumerator(start, enumerateSiblings);
while (tne.MoveNext())
{
yield return(tne.Current);
}
}
/// <summary>
/// Enumerate just the selected node (branch) and, based on the sender, the subsequent siblings
/// </summary>
/// <param name="sender">The sender of the event</param>
/// <param name="e">The event arguments</param>
private void btnEnumNode_Click(object sender, EventArgs e)
{
#region TreeNodeEnumerator Example
bool enumerateSiblings = (sender == btnEnumNodeSibs);
TreeNode node, startNode = tvExtTree.SelectedNode;
if(startNode == null)
{
txtEnumResults.Text = "Select a starting node first";
return;
}
txtEnumResults.Text = null;
// For this, we create the enumerator manually and pass it
// the starting node and a flag indicating whether or not
// to enumerate the siblings of the starting node as well.
TreeNodeEnumerator enumerator = new TreeNodeEnumerator(startNode,
enumerateSiblings);
// Call the MoveNext() method to move through each node. Use the
// Current property to access the current node.
while(enumerator.MoveNext())
{
node = enumerator.Current;
txtEnumResults.AppendText(String.Format("Manual Enum: {0}{1}\r\n",
new String(' ', node.Level * 4), node.Text));
}
txtEnumResults.AppendText("\r\n\r\n");
// We can also use the helper method to simplify it
foreach(TreeNode tn in TreeNodeEnumerator.Enumerate(startNode, enumerateSiblings))
txtEnumResults.AppendText(String.Format("Enum Helper: {0}{1}\r\n",
new String(' ', tn.Level * 4), tn.Text));
#endregion
}
//=====================================================================
/// <summary>
/// This method can be used to enumerate tree nodes in a more convenient way using a <c>foreach</c>
/// loop without having to manually construct and manage the enumerator.
/// </summary>
/// <param name="start">The node at which to start enumeration.</param>
/// <param name="enumerateSiblings">True to enumerate the starting node's siblings as well or false to
/// stop after enumerating the starting node and all of its children.</param>
/// <returns>An enumerable list of tree nodes</returns>
public static IEnumerable<TreeNode> Enumerate(TreeNode start, bool enumerateSiblings)
{
var tne = new TreeNodeEnumerator(start, enumerateSiblings);
while(tne.MoveNext())
yield return tne.Current;
}