Untitled

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Send to Whatsapp</title>
    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/sweetalert/1.1.3/sweetalert.min.css">
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/css/bootstrap.min.css" integrity="sha384-PsH8R72JQ3SOdhVi3uxftmaW6Vc51MKb0q5P2rRUpPvrszuE4W1povHYgTpBfshb" crossorigin="anonymous">

</head>
<body>
    <nav class="navbar navbar-expand-lg navbar-light bg-light">
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon"></span>
        </button>

        <div class="collapse navbar-collapse" id="navbarSupportedContent">
            <ul class="navbar-nav mr-auto">
                <li class="nav-item active">
                    <a class="nav-link" href="#">Send To Whatsapp <span class="sr-only">(current)</span></a>
                </li>
            </ul>
        </div>
    </nav>

    <div class="jumbotron vertical-center">
    <div class="container center">
        <div class="row">
            <div class="col-xs-12 col-md-6 col-md-offset-6">
                <h2>Send Message to Whatsapp</h2>
                <form>
                    <div class="form-group">
                        <label for="phone">Phone number</label>
                        <input type="number" name="phone" id="phone" class="form-control" placeholder="6281515339555">
                    </div>
                    <div class="form-group">
                        <label for="text">Text</label>
                        <textarea class="form-control" name="text" id="text"></textarea>
                    </div>
                    <button type="button" class="btn btn-primary col-xs-12" id="send">Send</button>
                </form>
            </div>
        </div>
    </div>
    </div>
</body>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/sweetalert/1.1.3/sweetalert.min.js"></script>
<script>
    $(document).ready(function(){
        var btnSend = $('#send');
        btnSend.click(function (){
            var phone = $('#phone').val();
            if (!phone) {
                swal('Please enter a phone number');
                return;
            }
            var text = $('#text').val();
            if (!text) {
                swal("Please enter message");
                return;
            }
            var url = 'http://api.whatsapp.com/send?phone='+ phone + '&text=' + text;
            var win = window.open(url , '_blank');
            win.focus();
        });
    });
</script>
</html>