从特定行开始，打印与模式匹配的周围行

import re

def print_surrounding_lines(file_path, start_line, pattern, num_lines):
    with open(file_path, 'r') as file:
        lines = file.readlines()

    start_index = start_line - 1
    pattern_regex = re.compile(pattern)

    for i in range(start_index, len(lines)):
        line = lines[i]
        if pattern_regex.search(line):
            start_index = max(0, i - num_lines)
            end_index = min(len(lines), i + num_lines + 1)
            for j in range(start_index, end_index):
                print(lines[j].strip())

file_path = 'example.log'  # 替换为实际的日志文件路径
start_line = 10  # 替换为实际的起始行数
pattern = 'error'  # 替换为实际的模式
num_lines = 2  # 替换为实际的周围行数

print_surrounding_lines(file_path, start_line, pattern, num_lines)