دریافت اعداد درtextbox

    <script type="text/javascript">
        $(document).on("input", ".numeric", function () {
            this.value = this.value.replace(/\D/g, '');
        });
    </script>


<asp:TextBox runat="server" MaxLength="4" TextMode="Number" ID="txtYear" placeholder="مثال: 1398" required></asp:TextBox>