@(Html.Kendo().PDFViewer()
    .Name("test")
    .PdfjsProcessing(pdf => pdf.File(""))
        .Toolbar(t => t.Items(i =>
            {
            i.Add().Name("Open").Id("Open").Command("OpenCommand").Type("button").Icon("folder-open");
            i.Add().Name("Print").Id("Print").Type("button").Icon("print").Click("onPrintClick");
        }))
        .Height(500)
)

<script>
   function onPrintClick(e) {
        alert(e);
    }
</script>