# Serial.readBytes(buffer, length)

### 参数

| 参数名    | 描述                          |
| ------ | --------------------------- |
| buffer | 用来存储字节（char\[]或byte\[]）的缓冲区 |
| length | 读取的字节数（int）                 |

### 返回

| 参数名    | 描述                            |
| ------ | ----------------------------- |
| number | 返回放置在缓冲区的字符数。返回0意味着没有发现有效的数据。 |


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