在金额对象paypal 2019中添加值变量

Question

I'm creating an order using paypal API. I need to put the value of an item inside the "amount" object, as is provided by the example code in the paypal page. The code is as follows:

paypal.Buttons({
    createOrder: function(data, actions) {
      // Set up the transaction
      return actions.order.create({
        purchase_units: [{
          amount: {
            value: '0.01'
          }
        }]
      });
    }
  }).render('#paypal-button-container');

I need to pass the value (currently shown as 0.01) from a select field that is inside a form above. I'm also concerned the security issues related with the front end ¿taking a variable from a form, storing into a variable and then pass it to an object could let the value exposed to being altered? I'm trying to find a flow where I jump from my form to a handler in php, but this step that paypal does in the front end calling paypal website and passing variables from the form doesn't suit me at all...

Maybe the flow "fill form- pass values to variables - pass variables to paypal object that does the call to paypal web" is not the adequate..

Answer 1

you can declare an variable, let amount = 0; upon the from value change the amount variable and use like this, im assuming that you take value from an form

// if in js var amount = 0;

 $("#myTextBox").on("change paste keyup", function() {  
   amount = $(this).val();  
 });


paypal.Buttons({
    createOrder: function(data, actions) {
      // Set up the transaction
      return actions.order.create({
        purchase_units: [{
          amount: {
            value: amount
          }
        }]
      });
    }
  }).render('#paypal-button-container');