CODE EXAMPLE FOR JAVASCRIPT

URLSearchParams for query params

import React, { useEffect, useState } from "react";
import { useLocation } from "react-router-dom";

function CheckoutDetails() {
  const location = useLocation();
  const [amountValue, setAmountValue] = useState(1);

  // function to get query params using URLSearchParams
  useEffect(() => {
    const searchParams = new URLSearchParams(location.search);
    if (searchParams.has("amount")) {
      const amount = searchParams.get("amount");
      setAmountValue(parseInt(amount, 10));
    } else {
      setAmountValue(1);
    }
  }, [location]);

  return (
  	<p>Amount: {amountValue}</p>
  )