Python如何匹配文本并在其上一行追加文本

2024-04-02 19:04:59 714人浏览泡泡鱼

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摘要

目录匹配文本并在其上一行追加文本问题描述对比遇到的坑用正则表达式匹配文本(python经典编程案例)匹配文本并在其上一行追加文本问题描述 Python匹配文本并在其上一行追加文本

匹配文本并在其上一行追加文本

问题描述

Python匹配文本并在其上一行追加文本

test.txt

a
b
c
d
e

1.读进列表后覆盖原文件

def match_then_insert(filename, match, content):
    """匹配后在该行追加
    :param filename: 要操作的文件
    :param match: 匹配内容
    :param content: 追加内容
    """
    lines = open(filename).read().splitlines()
    index = lines.index(match)
    lines.insert(index, content)
    open(filename, mode='w').write('\n'.join(lines))
match_then_insert('test.txt', match='c', content='123')

效果

a
b
123
c
d
e

2.FileInput类

from fileinput import FileInput
def match_then_insert(filename, match, content):
    """匹配后在该行追加
    :param filename: 要操作的文件
    :param match: 匹配内容
    :param content: 追加内容
    """
    for line in FileInput(filename, inplace=True):  # 原地过滤
        if match in line:
            line = content + '\n' + line
        print(line, end='')  # 输出重定向到原文件
match_then_insert('test.txt', match='c', content='123')

3.seek

def match_then_insert(filename, match, content):
    """匹配后在该行追加
    :param filename: 要操作的文件
    :param match: 匹配内容
    :param content: 追加内容
    """
    with open(filename, mode='rb+') as f:
        while True:
            try:
                line = f.readline()  # 逐行读取
            except IndexError:  # 超出范围则退出
                break
            line_str = line.decode().splitlines()[0]
            if line_str == match:
                f.seek(-len(line), 1)  # 光标移动到上一行
                rest = f.read()  # 读取余下内容
                f.seek(-len(rest), 1)  # 光标移动回原位置
                f.truncate()  # 删除余下内容
                content = content + '\n'
                f.write(content.encode())  # 插入指定内容
                f.write(rest)  # 还原余下内容
                break
match_then_insert('test.txt', match='c', content='123')

对比

方案	耗时/s
读进列表后覆盖原文件	54.42
FileInput类	121.59
seek	3.53

from timeit import timeit
from fileinput import FileInput
def init_txt():
    open('test.txt', mode='w').write('\n'.join(['a', 'b', 'c', 'd', 'e']))
def f1(filename='test.txt', match='c', content='123'):
    lines = open(filename).read().splitlines()
    index = lines.index(match)
    lines.insert(index, content)
    open(filename, mode='w').write('\n'.join(lines))
def f2(filename='test.txt', match='c', content='123'):
    for line in FileInput(filename, inplace=True):
        if match in line:
            line = content + '\n' + line
        print(line, end='')
def f3(filename='test.txt', match='c', content='123'):
    with open(filename, mode='rb+') as f:
        while True:
            try:
                line = f.readline()
            except IndexError:
                break
            line_str = line.decode().splitlines()[0]
            if line_str == match:
                f.seek(-len(line), 1)
                rest = f.read()
                f.seek(-len(rest), 1)
                f.truncate()
                content = content + '\n'
                f.write(content.encode())
                f.write(rest)
                break
init_txt()
print(timeit(f1, number=1000))
init_txt()
print(timeit(f2, number=1000))
init_txt()
print(timeit(f3, number=1000))

遇到的坑

报错可试试在文件头部添加

# -*- coding: utf-8 -*-

或指定 encoding='utf-8'

用正则表达式匹配文本(Python经典编程案例)

ceshi.txt文本如下：第一行为空行


爬虫任务报警
01:45:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-1
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: ah_sina_com_cn,job: 28395818dbcb11e998a3f632d94e247c,pid: 88971,log: data/logs/chinabond_fast_spider/ah_sina_com_cn/28395818dbcb11e998a3f632d94e247c.log,items: None
error_data:
爬虫任务报警
01:45:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-6
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: shupeidian_bjx_com_cn,job: 04738a5cdbcb11e9803172286b76aa73,pid: 34246,log: data/logs/chinabond_fast_spider/shupeidian_bjx_com_cn/04738a5cdbcb11e9803172286b76aa73.log,items: None
error_data:
爬虫任务报警
01:45:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-6
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: news_sdchina_com,job: 28e8db4edbcb11e9803172286b76aa73,pid: 34324,log: data/logs/chinabond_fast_spider/news_sdchina_com/28e8db4edbcb11e9803172286b76aa73.log,items: None
error_data:
爬虫任务报警
01:47:20
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-0
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: hq_smm_cn,job: 4bdc3af6dbcb11e9a45522b8c8b2a9e4,pid: 111593,log: data/logs/chinabond_fast_spider/hq_smm_cn/4bdc3af6dbcb11e9a45522b8c8b2a9e4.log,items: None
error_data:
爬虫任务报警
01:47:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-6
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: sichuan_scol_com_cn,job: 71321c4edbcb11e9803172286b76aa73,pid: 34461,log: data/logs/chinabond_fast_spider/sichuan_scol_com_cn/71321c4edbcb11e9803172286b76aa73.log,items: None
error_data:
爬虫任务报警
01:47:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-2
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: www_mof_Gov_cn,job: 7418dacedbcb11e9b15e02034af50b6e,pid: 65326,log: data/logs/chinabond_fast_spider/www_mof_gov_cn/7418dacedbcb11e9b15e02034af50b6e.log,items: None
error_data:
爬虫任务报警
01:47:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-5
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: www_funxun_com,job: 4dcda7a0dbcb11e980a8862f09ca6d70,pid: 27785,log: data/logs/chinabond_fast_spider/www_funxun_com/4dcda7a0dbcb11e980a8862f09ca6d70.log,items: None
error_data:
爬虫任务报警
01:49:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-4
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: shuidian_bjx_com_cn,job: 95090682dbcb11e9a0fade28e59e3773,pid: 106424,log: data/logs/chinabond_fast_spider/shuidian_bjx_com_cn/95090682dbcb11e9a0fade28e59e3773.log,items: None
error_data:
爬虫任务报警
01:51:20
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-0
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: tech_sina_com_cn,job: de4bdf72dbcb11e9a45522b8c8b2a9e4,pid: 111685,log: data/logs/chinabond_fast_spider/tech_sina_com_cn/de4bdf72dbcb11e9a45522b8c8b2a9e4.log,items: None
error_data:
爬虫任务报警
01:51:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-6
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: ee_ofweek_com,job: ff6bd5b8dbcb11e9803172286b76aa73,pid: 34626,log: data/logs/chinabond_fast_spider/ee_ofweek_com/ff6bd5b8dbcb11e9803172286b76aa73.log,items: None
error_data:
爬虫任务报警
01:51:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-6
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: house_hexun_com,job: ff6dfdacdbcb11e9803172286b76aa73,pid: 34633,log: data/logs/chinabond_fast_spider/house_hexun_com/ff6dfdacdbcb11e9803172286b76aa73.log,items: None
error_data:
爬虫任务报警
01:51:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-2
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: www_sjfzxm_com,job: 018e7d78dbcc11e9b15e02034af50b6e,pid: 65492,log: data/logs/chinabond_fast_spider/www_sjfzxm_com/018e7d78dbcc11e9b15e02034af50b6e.log,items: None
error_data:
爬虫任务报警
01:53:21
scrapyd==》爬虫任务异常死亡报警
hostname: scrapyd-chinabond-4
error_count: Process died: exitstatus=None ,project: chinabond_fast_spider,spider: news_xianzhaiwang_cn,job: 48d835e8dbcc11e9a0fade28e59e3773,pid: 106476,log: data/logs/chinabond_fast_spider/news_xianzhaiwang_cn/48d835e8dbcc11e9a0fade28e59e3773.log,items: None
error_data:

代码如下：

import os
import re
import JSON
from collections import namedtuple
alert = namedtuple('Spider_Alert', 'alert_time, alert_hostname, alert_project, alert_spider')
path = r'D:\data\ceshi.txt'
g_path = r'D:\data\\'
file_name = r'result.txt'
file_path = g_path + file_name
alerts_list = list()
with open(path, encoding="utf-8") as file:
    lines = file.readlines()  # 读取每一行
    count = 0
    time = None
    hostname = None
    project = None
    for line in lines:
        if re.search(r'^\d{2}:\d{2}:\d{2}\s*$', line):
            time = re.search(r'^(\d{2}:\d{2}:\d{2})\s*$', line).group(1)
        if re.search(r'^hostname:\s*(.+)', line):
            hostname = re.search(r'^hostname:\s*(.+)', line).group(1)
        if re.search(r'project:\s*([^,]+),', line):
            project = re.search(r'project:\s*([^,]+),', line).group(1)
        if re.search(r'spider:\s*([^,]+),', line):
            spider = re.search(r'spider:\s*([^,]+),', line).group(1)
        if re.search(r'^error_data', line):
            spider_alert = None
            spider_alert = alert(alert_time=time, alert_hostname=hostname, alert_project=project, alert_spider=spider)
            alerts_list.append(spider_alert)
for element in alerts_list:
    print(element[0], element[1], element[3])
    with open(file_path, 'a', encoding="utf-8") as file:
        file.write(element[0] + "\t" + element[1] + "\t" + element[3])
        file.write(' \n')

执行结果如下图：