<asp:HiddenField ID="latTextBox" OnValueChanged="Unnamed_ValueChanged" runat="server"/>
             <asp:HiddenField ID="lonTextBox" runat="server"/>
             <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.2/jquery.min.js"></script>
            <%if (!IsPostBack) { %>
            <script type="text/javascript" id="getCord">
                if (typeof navigator.geolocation === 'undefined') {
                    alert("Geolocation services are not supported by your web browser");
                }
                else {
                    navigator.geolocation.getCurrentPosition(handleLocation, handleError);
                }

                function handleLocation(position) {
                        var lon = position.coords.longitude;
                        document.getElementById('<%= lonTextBox.ClientID %>').value = lon;
                        var lat = position.coords.latitude;
                        document.getElementById('<%= latTextBox.ClientID %>').value = lat;
                        __doPostBack('lonTextBox', 'TextChanged');

                }

                function handleError(error) {
                    switch (error.code) {
                        case error.TIMEOUT:
                            alert('Timeout');
                            break;
                        case error.POSITION_UNAVAILABLE:
                            alert('Position unavailable');
                            break;
                        case error.PERMISSION_DENIED:
                            alert('Permission denied');
                            break;
                        case error.UNKNOWN_ERROR:
                            alert('Unknown error');
                            break;
                    }
                }

            </script>
            <%} %>