我的代码
https://codesandbox.io/s/focused-thompson-w7v9c2?file=/index.tsx

<Formik
        initialValues={initialValues}
        onSubmit={async (values) => {
          await new Promise((r) => setTimeout(r, 500));
          // alert(JSON.stringify(values, null, 2));
          values.product.map((item, i: number) => {
            let qty: number[] = [];
            console.log(i + "-------qty------");
            console.log(item.qty);
            console.log(i + "-------price------");
            console.log(item.price);

            if (item.qty! && item.price!) {
              qty[i] = item.qty * item.price;

              console.log(qty);
            }
              const result = qty.reduce((sum, number) => {
                return sum + number;
              }, 0);
              setSum(result)
            console.log("-------result------");
            console.log(result);

            console.log("-------Sum------");
            console.log(sum);
            console.log("-------langth------");
            console.log(i);
          });
        }}
      >

我把价格和数量加到连续数组中。我需要price + qty组合，但是结果数组[ undefined, 30]或[undefined,undefined ,40]当我把数据加到数组中时，我想记录在const [sum, setSum] = useState(0)中