how to get the current location in javascript code example

Example: check the current location using js

var x = document.getElementById("demo");
    function getLocation() {
        if (navigator.geolocation) {
            navigator.geolocation.getCurrentPosition(showPosition, function (error) {
                var x = document.getElementById("demo");
                switch(error.code) {
                    case error.PERMISSION_DENIED:
                        x.innerHTML = "User denied the request for Geolocation."
                        break;
                    case error.POSITION_UNAVAILABLE:
                        x.innerHTML = "Location information is unavailable."
                        break;
                    case error.TIMEOUT:
                        x.innerHTML = "The request to get user location timed out."
                        break;
                    case error.UNKNOWN_ERROR:
                        x.innerHTML = "An unknown error occurred."
                        break;
                }
            });
        } else {
            var x = document.getElementById("demo");
            x.innerHTML = "Geolocation is not supported by this browser.";
        }
    }

    function showPosition(position) {
        var x = document.getElementById("demo");
        x.innerHTML = "Latitude: " + position.coords.latitude +
            "<br>Longitude: " + position.coords.longitude;
    }