Use the collection¶

Count the objects in a collection

Collections have the count property, an integer variable that expresses the amount of objects in the collection.

Below is an example of code that generates a message communicating the amount of child nodes of the Panel1 object:

var myObj = Project.Current.FindObject("Panel1");
Log.Info("The node contains " + myObj.Children.Count + " nodes");

Iterate the objects in a collection

Using the foreach instruction, it is possible to iterate the objects in a collection.

In the following example a code generates an information message for each child node of the Panel1 object. The result is a list of the BrowseName for all the child nodes.

Note

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/remove OPC UA nodes

Collections express two methods Add() and Remove() to add/remove project nodes. See API to add/remove nodes.