How to validate in the input text X and Y letters only from Jquery or HTML5

Question

I try to validate in the text box X and Y letters only for the NIC field. But it's not working. I need to block other letters without X and Y.

Example like this - 881161537V , 881161537X

This is Sri Lankan NIC format.

I appreciate your help. Many thanks!

Answer 1

HTML

<input type="text" name="number">

JS

$("input[name='number']").on('keydown', function(e) {
    var key = e.keyCode ? e.keyCode : e.which;
    //alert(key);
    if (!([8, 9, 13, 27, 46, 110, 190,17, 89, 88].indexOf(key) !== -1 ||
            (key == 65 && (e.ctrlKey || e.metaKey)) ||
            (key >= 35 && key <= 40) ||
            (key >= 48 && key <= 57 && !(e.shiftKey || e.altKey)) ||
            (key >= 96 && key <= 105)
        )) e.preventDefault();

});

Working Fiddle