How can i make a text input to start the number 9?

Question

I need a textbox to start with the number 9, how do i do it? The textbox only accepts numbers but i need it to start with the number 9. I've tried it like this but it doesn't work.

$(document).ready(function () { 
            var $phone = $("#phone");
            $phone.mask('900000000', {reverse: false});
        });

Answer 1

 $(function(){ //get the input element to const const $phn = $('#phone'); //add keydown event //if value is a length of 1 and code is backspace or delete return false //if length is longer than 1 and delete key is pressed, reset to just 9 $phn.on('keydown', function(e){ const code = e.which || e.keyCode; //keycode 8 = backspace, keycode 46 = delete if($phn.val().length === 1 && (code === 8 || code === 46)){ return false; } else if(code === 46){ $phn.val('9'); placeCursor($phn); } }); //initialize value to 9 and place cursor $phn.val('9'); placeCursor($phn); //function to focus and place cursor in input box function placeCursor(input){ $(input)[0].focus(); $(input)[0].setSelectionRange($(input).val().length, $(input).val().length); } });

 <input type="text" id="phone" /> <script src="https://code.jquery.com/jquery-3.6.0.slim.min.js" integrity="sha256-u7e5khyithlIdTpu22PHhENmPcRdFiHRjhAuHcs05RI=" crossorigin="anonymous"></script>

Answer 2

if(Number(text[0]) === 9) console.log('Ok');