1) Initialize the library

                  
<script src="https://pay.sandbox.datatrans.com/upp/payment/js/paypal-button-1.0.0.js" type="text/javascript"></script>
                

                  
PayPalButton.init({
 merchantId: '1100025160',
 reqType: 'CAA',
 currencyCode: 'CHF',
 amount: '100',
 createAlias: false
});
                  
                

2) Listen for the init event and create the button

                  
const configuration = {
 paypaloptions: {
   button: {
    layout: 'vertical',
    color: 'blue',
    shape: 'rect',
    label: 'paypal'
   }
  }, 
  transaction: { 
   refno: myReferenceNumber,
   authenticationOnly: false,
   returnAddress: true 
  }
}
                
PayPalButton.on("init", function () {
 PayPalButton.create(document.getElementById("paypalbutton"), configuration);
})
                  
                

3) Listen for the authorization event and continue

                    
PayPalButton.on("authorization", function (data) {
  // handle transaction result
});