test

<div id="smart-button-container">
<div style="text-align: center"><label for="description">Total amount of your registration </label><input
type="text" name="descriptionInput" id="description" maxlength="127" value=""></div>
<p id="descriptionError" style="visibility: hidden; color:red; text-align: center;">Please enter a description</p>
<div style="text-align: center"><label for="amount"> </label><input name="amountInput" type="number"
id="amount" value="" ><span> EUR</span></div>
<p id="priceLabelError" style="visibility: hidden; color:red; text-align: center;">Please enter a price</p>
<div id="invoiceidDiv" style="text-align: center; display: none;"><label for="invoiceid"> </label><input
name="invoiceid" maxlength="127" type="text" id="invoiceid" value="" ></div>
<p id="invoiceidError" style="visibility: hidden; color:red; text-align: center;">Please enter an Invoice ID</p>
<div style="text-align: center; margin-top: 0.625rem;" id="paypal-button-container"></div>
</div>
<script src="https://www.paypal.com/sdk/js?client-id=sb&enable-funding=venmo&currency=EUR" data-sdk-
integration-source="button-factory"></script>
<script>
function initPayPalButton() {
var description = document.querySelector('#smart-button-container #description');
var amount = document.querySelector('#smart-button-container #amount');
var descriptionError = document.querySelector('#smart-button-container #descriptionError');
var priceError = document.querySelector('#smart-button-container #priceLabelError');
var invoiceid = document.querySelector('#smart-button-container #invoiceid');
var invoiceidError = document.querySelector('#smart-button-container #invoiceidError');
var invoiceidDiv = document.querySelector('#smart-button-container #invoiceidDiv');

var elArr = [description, amount];

if (invoiceidDiv.firstChild.innerHTML.length > 1) {
invoiceidDiv.style.display = "block";
}

var purchase_units = [];
purchase_units[0] = {};
purchase_units[0].amount = {};

function validate(event) {
return event.value.length > 0;
}

paypal.Buttons({
style: {
color: 'gold',
shape: 'rect',
label: 'paypal',
layout: 'vertical',

},

onInit: function (data, actions) {
actions.disable();

if(invoiceidDiv.style.display === "block") {
elArr.push(invoiceid);
}

elArr.forEach(function (item) {
item.addEventListener('keyup', function (event) {
var result = elArr.every(validate);
if (result) {
actions.enable();
} else {
actions.disable();

}
});
});
},

onClick: function () {
if (description.value.length < 1) {
descriptionError.style.visibility = "visible";
} else {
descriptionError.style.visibility = "hidden";
}

if (amount.value.length < 1) {
priceError.style.visibility = "visible";
} else {
priceError.style.visibility = "hidden";
}

if (invoiceid.value.length < 1 && invoiceidDiv.style.display === "block") {
invoiceidError.style.visibility = "visible";
} else {
invoiceidError.style.visibility = "hidden";
}

purchase_units[0].description = description.value;
purchase_units[0].amount.value = amount.value;

if(invoiceid.value !== '') {
purchase_units[0].invoice_id = invoiceid.value;
}
},

createOrder: function (data, actions) {
return actions.order.create({
purchase_units: purchase_units,
});

},

onApprove: function (data, actions) {
return actions.order.capture().then(function (orderData) {

// Full available details
console.log('Capture result', orderData, JSON.stringify(orderData, null, 2));

// Show a success message within this page, e.g.
const element = document.getElementById('paypal-button-container');
element.innerHTML = '';
element.innerHTML = '<h3>Thank you for your payment!</h3>';

// Or go to another URL: actions.redirect('thank_you.html');

});
},

onError: function (err) {
console.log(err);
}
}).render('#paypal-button-container');
}
initPayPalButton();
</script>