> For the complete documentation index, see [llms.txt](https://javascriptuse.gitbook.io/javascript/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://javascriptuse.gitbook.io/javascript/problem-lay-key-dau-tien-tim-thay-chua-gia-tri-can-tim-ok.md).

# \[Problem] Lấy key đầu tiên tìm thấy chứa giá trị cần tìm (ok)

Bạn có thể sử dụng `Object.keys()` kết hợp với `find()` hoặc `filter()` để tìm key chứa giá trị cụ thể trong JavaScript. Dưới đây là cách làm:

#### Cách 1: Dùng `find()` (Trả về key đầu tiên tìm thấy)

```javascript
javascriptCopyEditconst ahash = { "one": [1, 2, 3], "two": [4, 5, 6] };

const targetNumbers = [4, 5, 6];
const key = Object.keys(ahash).find(k => ahash[k].some(num => targetNumbers.includes(num)));

console.log(key); // Kết quả: "two"
```

👉 **Lấy key đầu tiên tìm thấy chứa số cần tìm.**

***

#### Cách 2: Dùng `filter()` (Trả về tất cả các key phù hợp)

```javascript
javascriptCopyEditconst keys = Object.keys(ahash).filter(k => ahash[k].some(num => targetNumbers.includes(num)));

console.log(keys); // Kết quả: ["two"]
```

👉 **Trả về mảng chứa tất cả key thỏa mãn điều kiện.**

Bạn thích cách nào hơn? 🚀


---

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