Javascript 无法访问新筛选数组的属性

我试图访问新筛选数组的属性'allergies'，但它抛出一个错误'can't read property of undefined'。这是我的密码：

   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“allergies”

但是，当我编写

'typeOf（activePatients[0]）时，

会记录对象

这就是patients数组的外观：

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)

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这里可能有什么问题？非常感谢

你能在运行代码之前先把console.log（patients）写在这里吗？console.log（activePatients[0]）我的不好，已经编辑过帖子了！谢天谢地，这不是节点，你能截图浏览器的控制台吗？添加一个

在方括号前嵌入图像。我无法复制。您是否异步获取这些数据，比如从http请求或数据库？