JSFiddle - React, Tailwind, and code Playground

HTML

<input id="mobilenumber" class="form-control" type="text" value="" placeholder="Your Mobile Number" name="MobileNumber" data-val-maxlength-max="15" data-val-maxlength="Mobile number can not be longer then 15 characters" data-val="true">

JavaScript

$(document).ready(function () {

    $("#mobilenumber").keypress(isNumberKey);
    function isNumberKey() {
        alert('check');
        var charCode = (event.which) ? event.which : event.keyCode;
        if (charCode != 46 && charCode > 31 && (charCode < 48 || charCode > 57)) {
            event.preventDefault();
            return false;
        }
        return true;
    }
});