var input = document.querySelector("#registration-phone-number");

var errorMap = ["Invalid number", "Invalid country code", "Too short", "Too long", "Invalid number"];

    window.addEventListener("load", function () {

        errorMsg = document.querySelector("#error-msg"),

 validMsg = document.querySelector("#valid-msg");

        var iti = window.intlTelInput(input, {

            utilsScript:"./intl-tel-input/js/utils.js"

        });

        window.intlTelInput(input, {

            // allowDropdown: false,

            // autoHideDialCode: false,

            // autoPlaceholder: "off",

            // dropdownContainer: document.body,

            // excludeCountries: ["us"],

            // formatOnDisplay: false,

             geoIpLookup: function(callback) {

         $.get("https://ipinfo.io", function() {}, "jsonp").always(function(resp) {

           var countryCode = (resp && resp.country) ? resp.country : "";

           callback(countryCode);           

         });

       },

             hiddenInput: "full_number",

            initialCountry: "auto",

            // localizedCountries: { 'de': 'Deutschland' },

           // nationalMode: false,

            // onlyCountries: ['us', 'gb', 'ch', 'ca', 'do'],

            placeholderNumberType: "MOBILE",

            // preferredCountries: ['cn', 'jp'],

             separateDialCode: true,

            utilsScript: "./intl-tel-input/js/utils.js",

        });

        $(validMsg).hide();       

        input.addEventListener('blur', function () {

            reset();

            if (input.value.trim()) {

                if (iti.isValidNumber()) {                 

        $(validMsg).show();                 

                } else {                  

                    $(input).addClass('form-control-danger');

                    var errorCode = iti.getValidationError();

                    errorMsg.innerHTML = errorMap[errorCode];

                    $(errorMsg).show();

                }

            }

        });        

        input.addEventListener('change', reset);        

        input.addEventListener('keyup', reset);

    });

​

    var reset = function () {

        $(input).removeClass('form-control-danger');

        errorMsg.innerHTML = "";

        $(errorMsg).hide();

        $(validMsg).hide();

    };

​

​