2

单击此处获取控制台输出！

我正在尝试访问新过滤的数组的属性“过敏”，但它会引发错误“无法读取未定义的属性”。这是我的代码：

   let activePatients = patients.filter(patient => patient.mealPlans.length > 0);
console.log(activePatients); //this appears in the console!
console.log(activePatients[0]);  //this too!
console.log(activePatients[0].allergies); //this throws the following error

TypeError：无法读取未定义的属性“过敏”

但是，当我写'typeOf(activePatients[0])'它时，它会记录 Object.

这就是患者数组的样子：

0: {favoriteFoods: Array(0), dislikedFoods: Array(0), allergies: Array(0), mealPlans: Array(1), measurements: Array(0), …}
1: {favoriteFoods: Array(0), dislikedFoods: Array(0), allergies: Array(0), mealPlans: Array(1), measurements: Array(0), …}
2: {favoriteFoods: Array(0), dislikedFoods: Array(0), allergies: Array(0), mealPlans: Array(1), measurements: Array(0), …}
3: {favoriteFoods: Array(0), dislikedFoods: Array(0), allergies: Array(0), mealPlans: Array(1), measurements: Array(0), …}
4: {favoriteFoods: Array(0), dislikedFoods: Array(0), allergies: Array(0), mealPlans: Array(0), measurements: Array(0), …}
length: 5
__proto__: Array(0)

和 activePatients 数组：

0: {favoriteFoods: Array(0), dislikedFoods: Array(0), allergies: Array(0), mealPlans: Array(1), measurements: Array(0), …}
1: {favoriteFoods: Array(0), dislikedFoods: Array(0), allergies: Array(0), mealPlans: Array(1), measurements: Array(0), …}
2: {favoriteFoods: Array(0), dislikedFoods: Array(0), allergies: Array(0), mealPlans: Array(1), measurements: Array(0), …}
3: {favoriteFoods: Array(0), dislikedFoods: Array(0), allergies: Array(0), mealPlans: Array(1), measurements: Array(0), …}
length: 4
__proto__: Array(0)

这里可能是什么问题？非常感谢！

4

0 回答 0