arr.findIndex() returns -1

Question

恐怕这应该是显而易见的，因为我的事务是基于普通的Vanille JS。无论如何，无论出于什么原因，我都无法解决我的问题。有谁能帮我吗？

我在reducer:中的代码快照

> case TOGGLE_PRODUCT:
>       const newProducts = [...state.allProducts];
>       console.log("All products: ", newProducts);
>       console.log("Passed product: ", action.productId);
>       console.log("Should have found: ", newProducts[1]);
>       const toggledProduct = newProducts.findIndex(
>         (el) => el.id === action.productId
>       );
>       console.log("Found: ", toggledProduct);

控制台输出：

All products:  Array [
Product {
"amount": 0,
"department": "Molkereiprodukte",
"id": "id1",
"product": "Milch 3,5%",
"status": false,
},
Product {
"amount": 0,
"department": "Molkereiprodukte",
"id": "id2",
"product": "Yoghurt",
"status": false,
},
Product {
"amount": 0,
"department": "Ceralien",
"id": "id3",
"product": "Müsli",
"status": false,
},
]
Passed product:  Object {
"id": "id2",
}
Should have found:  Product {
"amount": 0,
"department": "Molkereiprodukte",
"id": "id2",
"product": "Yoghurt",
"status": false,
}
Found:  -1

为什么find((方法不返回结果？？？

提前Thx！

Answer 1

您的action.productId是object而不是string

const toggledProduct = newProducts.findIndex(
(el) => el.id === action.productId.id /** <--here */
);

Answer 2

findIndex用于查找需要Array.find才能获得元素数据的元素的期望索引。获得-1的原因是action.productId是一个对象。您需要比较action.productId.id

const toggledProduct = newProducts.find(el => el.id === action.productId.id );