Checkboxes - C1 ASP.NET MVC

// This file locates: "Scripts/Lesson/C1Nav/Checkboxes.js".
c1.documentReady(function () {
    var tree = wijmo.Control.getControl('#theTree');
 
    tree.showCheckboxes = true;
    tree.checkedItemsChanged.addHandler(function (s, e) {
        var items = s.checkedItems,
            msg = '';
        if (items.length) {
            msg = '<p><b>Checked Items:</b></p><ol>\r\n';
            for (var i = 0; i < items.length; i++) {
                msg += '<li>' + items[i].Header + '</li>\r\n';
            }
            msg += '</ol>';
        }
        document.getElementById('tvChkStatus').innerHTML = msg;
    });
 
    // handle buttons
    document.getElementById('btnCheckAll').addEventListener('click', function (e) {
        tree.checkAllItems(true);
    });
    document.getElementById('btnUncheckAll').addEventListener('click', function (e) {
        tree.checkAllItems(false);
    });
    document.getElementById('btnSaveState').addEventListener('click', function (e) {
        checkedItems = tree.checkedItems || [];
    });
    document.getElementById('btnRestoreState').addEventListener('click', function (e) {
        tree.checkedItems = checkedItems;
    });
});

// This file locates: "Content/css/Lesson/C1Nav/Checkboxes.css".
/* default trees on this sample */
.demo-control .wj-treeview {
    display:block;
    height: 350px;
    font-size: 120%;
    margin-bottom: 8px;
    padding: 6px;
    background: #f0f0f0;
    box-shadow: 0 3px 6px rgba(0,0,0,0.16), 0 3px 6px rgba(0,0,0,0.23);
}

using System.Web.Mvc;
 
namespace LearnMvcClient.Controllers
{
    public partial class C1NavController : Controller
    {
        // GET: Checkboxes
        public ActionResult Checkboxes()
        {
            return View(Models.TreeViewData.GetData(Url));
        }
    }
}

@model IEnumerable<TreeViewData>
 
<h1>
    @Html.Raw(Resources.C1Nav.Checkboxes_Title)
</h1>
 
<p>
    @Html.Raw(Resources.C1Nav.Checkboxes_Text1)
</p>
<p>
    @Html.Raw(Resources.C1Nav.Checkboxes_Text2)
</p>
<p>
    @Html.Raw(Resources.C1Nav.Checkboxes_Text3)
</p>
 
@Html.C1().TreeView().Id("theTree").Bind(Model).DisplayMemberPath("Header").ChildItemsPath("Items")
<button id="btnCheckAll" class="btn btn-default">
    @Html.Raw(Resources.C1Nav.Checkboxes_Text4)
</button>
<button id="btnUncheckAll" class="btn btn-default">
    @Html.Raw(Resources.C1Nav.Checkboxes_Text5)
</button>
  &nbsp;&nbsp;&nbsp;&nbsp;
<button id="btnSaveState" class="btn btn-default">
    @Html.Raw(Resources.C1Nav.Checkboxes_Text6)
</button>
<button id="btnRestoreState" class="btn btn-default">
    @Html.Raw(Resources.C1Nav.Checkboxes_Text7)
</button>
 
<div id="tvChkStatus"></div>

Node Checkboxes