public static void AddScript(System.Web.UI.Page page, string src, bool top = true, bool defer = false, bool asnc = false) { var d = defer ? " defer=\"defer\"" : ""; var a = asnc ? " async=\"async\"" : ""; var t = "\n<script type=\"text/javascript\" src=\"{0}\"{1}{2}></script>"; t = string.Format(t, src, d, a); if (top) { page.Header.Controls.Add(new LiteralControl(t)); } else { page.ClientScript.RegisterStartupScript(page.GetType(), src.GetHashCode().ToString(), t, false); } }