public class HtmlElementCollection : System.MarshalByRefObject 

using System;
using Zennolab.CommandCenter;
 
namespace Sample
{
    internal class Example
    {
        public static int Execute(Instance instance)
        {
            instance.ClearCookie();
 
            Tab tab = instance.MainTab;
            if ((tab.IsVoid) || (tab.IsNull)) return -1;
            if (tab.IsBusy) tab.WaitDownloading();
            tab.Navigate("lessons.zennolab.com");
            if (tab.IsBusy) tab.WaitDownloading();
 
            HtmlElementCollection heCol = tab.FindElementsByTags("input:checkbox");
            
            if ((heCol.IsVoid) || (heCol.ErrorDetected)) return -1;
            
            HtmlElement he = null;
            
            for (int i = 0; i < heCol.Count; i++)
            {
                he = heCol.Elements[i];
            }
 
            int index = heCol.IndexOf(he);
            
            return 0;
        }
    }
}

<?php
namespace System;
namespace Zennolab\CommandCenter;
 
class Example
{
    public static function Execute($instance)
    {
        $instance->ClearCookie();
 
        $tab = $instance->MainTab;
        if (($tab->IsVoid) || ($tab->IsNull)) return -1;
        if ($tab->IsBusy) $tab->WaitDownloading();
        $tab->Navigate("lessons.zennolab.com");
        if ($tab->IsBusy) $tab->WaitDownloading();
 
        $heCol = $tab->FindElementsByTags("input:checkbox");
            
        if (($heCol->IsVoid) || ($heCol->ErrorDetected)) return -1;
            
        for ($i = 0; $i < $heCol->Count; $i++)
        {
            $he = $heCol->Elements[$i];
        }
 
        $index = $heCol->IndexOf($he);
            
        return 0;
    }
}
?>