python判断文件使用什么编码方式编码的。

# 说明：UTF兼容ISO8859-1和ASCII，GB18030兼容GBK，GBK兼容GB2312，GB2312兼容ASCII
CODES = ['UTF-8', 'UTF-16', 'GB18030', 'BIG5']
# UTF-8 BOM前缀字节
UTF_8_BOM = b'\xef\xbb\xbf'




# 获取文件编码类型
def file_encoding(file_path):
    """
    获取文件编码类型\n
    :param file_path: 文件路径\n
    :return: \n
    """
    with open(file_path, 'rb') as f:
        return string_encoding(f.read())




# 获取字符编码类型
def string_encoding(b: bytes):
    """
    获取字符编码类型\n
    :param b: 字节数据\n
    :return: \n
    """
    # 遍历编码类型
    for code in CODES:
        try:
            b.decode(encoding=code)
            if 'UTF-8' == code and b.startswith(UTF_8_BOM):
                return 'UTF-8-SIG'
            return code
        except Exception:
            continue
    return '未知的字符编码类型'
if __name__ == '__main__':
    encoding = file_encoding('2.txt')
    print(encoding)