# Block 이 체결될때마다 event 를 받을 수 있는 방법이 있을까요?

**URL:** <https://devforum.kaia.io/t/block-event/1936>\
**Category:** Kaia\
**Tags:** caver-js, klaytn\
**Created:** [9월 28, 2021, 4:19오전 UTC](https://devforum.kaia.io/t/block-event/1936 "2021-09-28T04:19:06Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![namu](https://avatars.discourse-cdn.com/v4/letter/n/bbe5ce/32.png) [@namu](https://devforum.kaia.io/u/namu)\
**Post date:** [9월 28, 2021, 4:19오전 UTC](https://devforum.kaia.io/t/block-event/1936/1 "2021-09-28T04:19:06Z")

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안녕하세요,

klaytn 문서상으로는 JSON RPC api 를 이용하면 block number 를 가져올 수 있는데요 ([링크](https://ko.docs.klaytn.com/bapp/json-rpc/api-references/klay/block#klay_blocknumber)),  
이를 websocket 을 활용해 event 로 받을 수 있는 방법이 있나요?

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<div class="post-metadata">

**Author:** ![benjioh5](https://yyz1.discourse-cdn.com/flex035/user_avatar/devforum.kaia.io/benjioh5/32/293_2.png) [@benjioh5](https://devforum.kaia.io/u/benjioh5)\
**Post date:** [9월 28, 2021, 5:08오전 UTC](https://devforum.kaia.io/t/block-event/1936/2 "2021-09-28T05:08:18Z")

</div>

> **[Filter](https://docs.klaytn.com/bapp/json-rpc/api-references/klay/filter#klay_subscribe)**

에서 websocket 기반으로 subscribe를 하시면 됩니다

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<div class="post-metadata">

**Author:** ![Jamie](https://yyz1.discourse-cdn.com/flex035/user_avatar/devforum.kaia.io/jamie/32/1472_2.png) [@Jamie](https://devforum.kaia.io/u/Jamie)\
**Post date:** [9월 28, 2021, 5:57오전 UTC](https://devforum.kaia.io/t/block-event/1936/3 "2021-09-28T05:57:46Z")

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간단한 예제 첨부합니다.

```
caver.rpc.klay.subscribe('newBlockHeaders', (error, event) => {
    if (error) {
        // error handling
    }

    console.log(`New Block Headers: ${caver.utils.hexToNumber(event.number)}`)
})
```

---

<div class="post-metadata">

**Author:** ![David](https://yyz1.discourse-cdn.com/flex035/user_avatar/devforum.kaia.io/david/32/960_2.png) [@David](https://devforum.kaia.io/u/David)\
**Post date:** [11월 12, 2021, 8:24오전 UTC](https://devforum.kaia.io/t/block-event/1936/4 "2021-11-12T08:24:11Z")

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브라우저 환경 말고 해당 코드를 커맨드 라인에서 user interrupt 있을때 까지 계속 대기하게 하면서 실행되게 하려면 어떻게 해야 할 까요??