Pass additional parameter to paypal button url - paypal

Question

I created a paypal button to manage my subscriptions and I´m planning to use it with my own link. Im not using the javascript SDK
Pay now
I was able to find that you can pass the &custom=123 parameter
but when I fetch a single subscription with
https://api-m.paypal.com/v1/billing/subscriptions/123
I don´t see the value of custom but I do see it in the POST request to my IPN endpoint. that means Paypal is sending it.
how can I see this custom value in the subscription itself? thank you!

Answer 1

Either: change to using a JavaScript SDK subscribe button and provide your value in the createSubscription's custom_id field
Or: continue using the legacy Subscribe button/link and try querying a v1/payments sale or v2/payments capture using a completed transaction ID for the subscription (not a profile ID), which might map to containing that legacy Subscribe transaction's custom value

Answer 2

Try this
<button onclick="pay()">Pay now</button>
<script>
function pay() {
$.ajax({
url: "https://www.paypal.com/cgi-bin/webscr",
type: "get",
data: {
cmd: _s-xclick,
hosted_button_id: 0000,
custom: 123
},
success: function(response) {
//Do Something
},
error: function(xhr) {
//Do Something to handle error
}
});
}
</script>