Use a collection

You can count, iterate, add, and remove objects in a collection.

Count objects in a collection

The count property of a collection is an integer variable that expresses the numberof objects in the collection. This example shows the number of child nodes in the Panel1 object:
var myObj = Project.Current.FindObject("Panel1");
            Log.Info("The node contains " + myObj.Children.Count + " nodes");

Iterate objects in a collection

You can use the foreach instruction to iterate objects in a collection. This example generates an information message for each child node of the Panel1 object. The result is a list of the BrowseName for all child nodes. In the example, a temporary child variable is created, which represents a different child node in each cycle.
var myNode = Project.Current.Find("Panel1");
            foreach (var child in myNode.Children)
              Log.Info(child.BrowseName);

Add or remove OPC UA nodes

You can use the Add() and Remove() methods expressed by collections to add or remove project nodes. See Add or remove nodes.