> For the complete documentation index, see [llms.txt](https://poseidon.seaeye.cn/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://poseidon.seaeye.cn/evm/account/sign_message_hash-1.md).

# sign\_message\_hash

对消息哈希进行 EIP-191 签名。

## 方法定义

```python
def sign_message_hash(self, message_hash: HexBytes) -> Optional[SignedMessageData]
```

## 参数说明

| 参数            | 类型       | 说明      |
| ------------- | -------- | ------- |
| message\_hash | HexBytes | 待签名消息哈希 |

## 返回值

返回 SignedMessageData 对象,包含以下字段:

| 字段              | 类型              | 说明      |
| --------------- | --------------- | ------- |
| message\_hash   | HexBytes        | 消息哈希    |
| message         | None            | 原始消息(无) |
| signer          | ChecksumAddress | 签名者地址   |
| signature\_data | SignatureData   | 签名数据    |

SignatureData 包含以下字段:

| 字段        | 类型       | 说明     |
| --------- | -------- | ------ |
| signature | HexBytes | 完整签名   |
| r         | HexBytes | 签名 r 值 |
| s         | HexBytes | 签名 s 值 |
| v         | HexBytes | 签名 v 值 |

## 示例代码

```python
# 签名消息哈希
message_hash = HexBytes("0x...")
signed = account.sign_message_hash(message_hash)

if signed:
    print(f"Message Hash: {signed.message_hash.hex()}")
    print(f"Signer: {signed.signer}")
    print(f"Signature: {signed.signature_data.signature.hex()}")
```


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://poseidon.seaeye.cn/evm/account/sign_message_hash-1.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.