PDF Export in ASP.NET MVC Tree Grid Component

@(Html.EJS().TreeGrid("TreeGrid").DataSource((IEnumerable<object>)ViewBag.datasource)
      .Columns(col =>
       {
        col.Field("TaskId").HeaderText("Task ID").Width(90).TextAlign(Syncfusion.EJ2.Grids.TextAlign.Right).Add();
        col.Field("TaskName").HeaderText("Task Name").Width(180).Add();
        col.Field("StartDate").HeaderText("Start Date").Format("yMd").Type("date").TextAlign(Syncfusion.EJ2.Grids.TextAlign.Right).Width(120).Add();
        col.Field("Duration").HeaderText("Duration").Width(110).TextAlign(Syncfusion.EJ2.Grids.TextAlign.Right).Add();

       }).Height(220).ChildMapping("Children").TreeColumnIndex(1).Toolbar(new List<string>() { "PdfExport" })
         .AllowPdfExport().AllowPaging().PageSettings(page => page.PageSize(7)).ToolbarClick("toolbarClick")
         .Render()
)

<script>
    function toolbarClick(args) {
        if (args['item'].text === 'PDF Export') {
            var treegrid = document.getElementById("TreeGrid").ej2_instances[0];
            treegrid.pdfExport();
        }
    }
</script>

public IActionResult Index()
{
    var tree = TreeData.GetDefaultData();
    ViewBag.datasource = tree;
    return View();
}

@Html.EJS().TreeGrid("TreeGrid").DataSource((IEnumerable<object>)ViewBag.summaryData).ChildMapping("subtasks").TreeColumnIndex(1).GridLines(Syncfusion.EJ2.Grids.GridLine.Both).AllowPdfExport(true).Toolbar(new List<string> { "PdfExport" }).Height(400).Width("auto").Columns(col =>
{
   col.Field("ID").HeaderText("Order ID").Width(115).TextAlign(Syncfusion.EJ2.Grids.TextAlign.Left).Add();
   col.Field("Name").HeaderText("Shipment Name").Width(230).ClipMode(Syncfusion.EJ2.Grids.ClipMode.EllipsisWithTooltip).Add();
   col.Field("shipmentDate").HeaderText("Shipment Date").Width(135).Type("date").Format("yMd").TextAlign(Syncfusion.EJ2.Grids.TextAlign.Right).Add();
   col.Field("category").HeaderText("Category").Width(220).MinWidth(210).Add();
   col.Field("units").HeaderText("Total Units").Width(90).Type("number").TextAlign(Syncfusion.EJ2.Grids.TextAlign.Right).Add();
   col.Field("unitPrice").HeaderText("Unit Price($)").Width(100).Type("number").Format("C2").TextAlign(Syncfusion.EJ2.Grids.TextAlign.Right).Add();
   col.Field("price").HeaderText("Price($)").Width(140).Type("number").Format("C0").TextAlign(Syncfusion.EJ2.Grids.TextAlign.Right).Add();
}).Aggregates(agg => {
        agg.ShowChildSummary(false).Columns(col =>
        { col.Type("Custom").CustomAggregate("customAggregateFn").ColumnName("category").Format("C2").FooterTemplate("<span>Count of <input type='text' id='customers' /> : ${Custom}</span>").Add();}).Add();
}).PdfAggregateQueryCellInfo("formatPdfAggregateCell").DataBound("onDataBound").Render()
<script>
    let selectedCategory = 'Seafood';
    let categoryDropdown;

    const categoryOptions = [
        { food: 'Seafood' },
        { food: 'Dairy' },
        { food: 'Edible' },
        { food: 'Crystal' },
    ];

    function customAggregateFn(data) {
        const records = data.result ? data.result : data;
        return records.reduce((count, item) => {
            return item.category === selectedCategory ? count + 1 : count;
        }, 0);
    }

    function formatPdfAggregateCell(args) {
        if (args.column.headerText === 'Category') {
            args.value = `Count of ${selectedCategory} : ${args.data.category.Custom}`;
        }
    }

    function onDataBound() {
        if (categoryDropdown && categoryDropdown.element && categoryDropdown.element.classList.contains('e-dropdownlist')) {
            categoryDropdown.destroy();
        }

        categoryDropdown = new ej.dropdowns.DropDownList({
            dataSource: categoryOptions,
            fields: { value: 'food' },
            placeholder: 'Select a Category',
            width: '110px',
            value: selectedCategory,
            change: () => {
                setTimeout(() => {
                    if (categoryDropdown && categoryDropdown.value) {
                        selectedCategory = categoryDropdown.value.toString();
                        treeGridObj.refresh();
                    }
                }, 300);
            }
        });

        categoryDropdown.appendTo('#customers');
      }

      let treeGridObj;
      document.addEventListener('DOMContentLoaded', function () {
         treeGridObj = document.getElementById('TreeGrid').ej2_instances[0];
         treeGridObj.toolbarClick = function (args) {
               if (args.item.text === 'PDF Export') {
                  treeGridObj.pdfExport({ pageOrientation: 'Landscape' });
               }
         };
      });
</script>

public IActionResult Index()
{
    ViewBag.datasource = summaryData.GetDefaultData();
    return View();
}