JSFiddle - React, Tailwind, and code Playground

HTML

<input name="cc" id="creditCard">
<button id="submitButton" disabled>
Gönder
</button>

JavaScript

function validateCardNumber(number) {
    var regex = new RegExp("^[0-9]{16}$");
    if (!regex.test(number))
        return false;

    return luhnCheck(number);
}

function luhnCheck(val) {
    var sum = 0;
    for (var i = 0; i < val.length; i++) {
        var intVal = parseInt(val.substr(i, 1));
        if (i % 2 == 0) {
            intVal *= 2;
            if (intVal > 9) {
                intVal = 1 + (intVal % 10);
            }
        }
        sum += intVal;
    }
    return (sum % 10) == 0;
}

document.getElementById('creditCard').addEventListener('input', function() {
  document.getElementById('submitButton').disabled = !validateCardNumber(this.value);
});