สอบทราบเรื่องการใช้ paypal ส่วนของ Express Checkout Client-Side REST

<script src="https://www.paypalobjects.com/api/checkout.js"></script>

<div id="paypal-button-container"></div>

<script>

    // Render the PayPal button

    paypal.Button.render({

        // Set your environment

        env: 'sandbox', // sandbox | production

        // Specify the style of the button

        style: {
            layout: 'vertical',  // horizontal | vertical
            size:   'medium',    // medium | large | responsive
            shape:  'rect',      // pill | rect
            color:  'gold'       // gold | blue | silver | black
        },

        // Specify allowed and disallowed funding sources
        //
        // Options:
        // - paypal.FUNDING.CARD
        // - paypal.FUNDING.CREDIT
        // - paypal.FUNDING.ELV

        funding: {
            allowed: [ paypal.FUNDING.CARD, paypal.FUNDING.CREDIT ],
            disallowed: [ ]
        },

        // PayPal Client IDs - replace with your own
        // Create a PayPal app: https://developer.paypal.com/developer/applications/create

        client: {
            sandbox:    'AZDxjDScFpQtjWTOUtWKbyN_bDt4OgqaF4eYXlewfBP4-8aqX3PiV8e1GWU6liB2CUXlkA59kJXE7M6R',
            production: '<insert production client id>'
        },

        payment: function(data, actions) {
            return actions.payment.create({
                payment: {
                    transactions: [
                        {
                           amount: { total: '<?php echo $priec ;?>', currency: 'THB' }
                        }
                    ]
                }
            });
        },

        onAuthorize: function(data, actions) {
            return actions.payment.execute().then(function() {
                window.alert('Payment Complete!');
            });
        }

    }, '#paypal-button-container');

</script>