> 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_string.md).

# sign\_message\_string

对消息字符串进行签名。

## 方法定义

```python
def sign_message_string(self, message: str) -> Optional[SignedMessageData]
```

## 参数说明

| 参数      | 类型  | 说明       |
| ------- | --- | -------- |
| message | str | 待签名消息字符串 |

## 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         | str             | 原始消息  |
| 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
message = "Hello, Ethereum!"
signed = account.sign_message_string(message)

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