问题

我有一个对象：

```tsx
interface MYInterface {
  aaa: number;
  bbb: number;
  ccc?: number | undefined;
}

const myObject: MYInterface = {
  aaa: 0,
  bbb: 0,
  ccc: 132,
};

我想检查这个对象中的一些键是否满足某个条件！我正在使用类似以下的 Array.some(...)：

const res = ['aaa', 'bbb'].some((key) => myObject[key] > 0)

但是对于 myObject[key]，我收到了有关 TypeScript 的错误：

Element implicitly has an 'any' type because expression of type 'string' can't be used to index type 'MYInterface'.
  No index signature with a parameter of type 'string' was found on type 'MYInterface'.

我知道我试图做的是使用对象中的字符串键数组，但我的数组包含这些字符串键。我尝试将键强制转换为 keyof MYInterface，但没有成功！我遇到了很多其他错误。我该如何解决这个问题？

此外，我的对象非常庞大，在这里我仅使用3个属性来演示问题。

以防您想要测试。

<details>
<summary>英文:</summary>

I have an object: 

```tsx
interface MYInterface {
  aaa: number;
  bbb: number;
  ccc?: number | undefined;
}

const myObject: MYInterface = {
  aaa: 0,
  bbb: 0,
  ccc: 132,
};

I want to check if some keys in this object, satisfy a condition! I'm using Array.some(...) like below:

const res = ['aaa', 'bbb'].some((key) => myObject[key] > 0)

but for myObject[key] I'm getting a TypeScript error about:

Element implicitly has an 'any' type because expression of type 'string' can't be used to index type 'INxStateCounts'.
  No index signature with a parameter of type 'string' was found on type 'INxStateCounts'.

I know that what am I trying to do is checking array of strings (keys) with objects but my array contains those keys in string.

I have tried to cast key as keyof MYInterface but no luck! I was getting so many other errors. How can I fix this?

Also my object is very big, here I use 3 properties to demonstrate the issue.

Just in case if you want to test.

答案1

得分: 3

以下是您要的翻译：

只需在您的代码中使类型更具体，就像这样：

function someOf<T>(keys: (keyof T)[], obj: T): boolean {
  return keys.some((key) => obj[key] > 0)
}

const res = someOf(['aaa', 'bbb'], myObject);

function someOf<T>(keys: (keyof T)[], obj: T): boolean {
  return keys.some((key) => obj[key] > 0)
}

const res = someOf(['aaa', 'bbb'], myObject);

答案2

得分: 1

你可以像这样写：

```ts
const keys: Array<MYInterface的键类型> = ['aaa', 'bbb'];

const res = keys.some((key) => (myObject[key] !== undefined && myObject[key] > 0));

由于进行了undefined检查，某种原因需要使用感叹号!运算符。

<details>
<summary>英文:</summary>

You can write something like this:

```ts
const keys : Array&lt;keyof MYInterface&gt; = [&#39;aaa&#39;, &#39;bbb&#39;]

const res = keys.some((key) =&gt; (myObject[key] !== undefined &amp;&amp; myObject[key]! &gt; 0))

for some reason the bang ! operator is needed despite undefined checking.

答案3

得分: 0

如果您使用对象索引签名，您可能会得到您想要的结果。尝试：

interface MYInterface {
  [key: string]: number;
}

其他处理此问题的方法：如何在TypeScript中动态分配对象属性

interface MYInterface {
  [key:string]: number;
}
...

答案4

得分: 0

你可以添加 as const 以将其转换为元组类型。然后，key 参数的类型将变为 'aaa'|'bbb'，而不是字符串/任意类型。

const res = (['aaa', 'bbb'] as const).some((key) => myObject[key] > 0)

const res = (['aaa', 'bbb'] as const).some((key) => myObject[key] > 0)