{"id":1090794,"date":"2025-01-08T14:05:40","date_gmt":"2025-01-08T06:05:40","guid":{"rendered":"https:\/\/docs.pingcode.com\/ask\/ask-ask\/1090794.html"},"modified":"2025-01-08T14:05:43","modified_gmt":"2025-01-08T06:05:43","slug":"python%e4%b8%ad%e5%a6%82%e4%bd%95%e6%8c%89%e8%a1%8c%e9%80%86%e5%ba%8f%e8%af%bb%e5%8f%96%e6%96%87%e4%bb%b6-2","status":"publish","type":"post","link":"https:\/\/docs.pingcode.com\/ask\/1090794.html","title":{"rendered":"Python\u4e2d\u5982\u4f55\u6309\u884c\u9006\u5e8f\u8bfb\u53d6\u6587\u4ef6"},"content":{"rendered":"

\"Python\u4e2d\u5982\u4f55\u6309\u884c\u9006\u5e8f\u8bfb\u53d6\u6587\u4ef6\"<\/p>\n

\u5728Python\u4e2d\uff0c\u6309\u884c\u9006\u5e8f\u8bfb\u53d6\u6587\u4ef6\u7684\u5e38\u7528\u65b9\u6cd5\u5305\u62ec\u4f7f\u7528readlines()\u65b9\u6cd5\u8bfb\u53d6\u6587\u4ef6\u3001\u4f7f\u7528reversed()\u51fd\u6570\u8fdb\u884c\u9006\u5e8f\u3001\u4f7f\u7528deque\u8fdb\u884c\u9ad8\u6548\u9006\u5e8f<\/strong>\u3002\u5176\u4e2d\uff0c\u4f7f\u7528readlines()\u65b9\u6cd5\u7ed3\u5408reversed()\u51fd\u6570\u662f\u6700\u5e38\u89c1\u7684\u65b9\u5f0f\uff0c\u56e0\u4e3a\u5b83\u7b80\u5355\u6613\u7528\u4e14\u9002\u7528\u4e8e\u5927\u591a\u6570\u60c5\u51b5\u3002\u4e0b\u9762\u5c06\u8be6\u7ec6\u4ecb\u7ecd\u8fd9\u79cd\u65b9\u6cd5\u3002<\/p>\n<\/p>\n

\u9996\u5148\uff0c\u7b80\u5355\u4ecb\u7ecd\u4e00\u4e0b\u5982\u4f55\u4f7f\u7528readlines()\u65b9\u6cd5\u548creversed()\u51fd\u6570\u6765\u6309\u884c\u9006\u5e8f\u8bfb\u53d6\u6587\u4ef6\uff1a<\/p>\n<\/p>\n

with open('example.txt', 'r') as file:<\/p>\n
    lines = file.readlines()<\/p>\n
    for line in reversed(lines):<\/p>\n
        print(line.strip())<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u63a5\u4e0b\u6765\uff0c\u6211\u4eec\u6df1\u5165\u63a2\u8ba8\u5404\u79cd\u65b9\u6cd5\u7684\u8be6\u7ec6\u5b9e\u73b0\u548c\u9002\u7528\u573a\u666f\u3002<\/p>\n<\/p>\n
\u4e00\u3001\u4f7f\u7528readlines()\u65b9\u6cd5\u548creversed()\u51fd\u6570<\/h2>\n<\/p>\n
1. \u8bfb\u53d6\u6587\u4ef6<\/h3>\n<\/p>\n
readlines()\u65b9\u6cd5\u5c06\u6587\u4ef6\u4e2d\u7684\u6bcf\u4e00\u884c\u8bfb\u53d6\u5230\u4e00\u4e2a\u5217\u8868\u4e2d\u3002\u8fd9\u79cd\u65b9\u6cd5\u9002\u7528\u4e8e\u6587\u4ef6\u8f83\u5c0f\u7684\u60c5\u51b5\uff0c\u56e0\u4e3a\u5b83\u4f1a\u5c06\u6574\u4e2a\u6587\u4ef6\u5185\u5bb9\u52a0\u8f7d\u5230\u5185\u5b58\u4e2d\u3002<\/p>\n<\/p>\n
2. \u9006\u5e8f\u8bfb\u53d6<\/h3>\n<\/p>\n
\u4f7f\u7528reversed()\u51fd\u6570\u5bf9\u5217\u8868\u8fdb\u884c\u9006\u5e8f\u3002\u8fd9\u662fPython\u5185\u7f6e\u7684\u9ad8\u6548\u9006\u5e8f\u65b9\u6cd5\u3002<\/p>\n<\/p>\n
with open('example.txt', 'r') as file:<\/p>\n
    lines = file.readlines()<\/p>\n
    for line in reversed(lines):<\/p>\n
        print(line.strip())<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u4e2a\u65b9\u6cd5\u7b80\u5355\u6613\u7528\uff0c\u9002\u7528\u4e8e\u6587\u4ef6\u5185\u5bb9\u8f83\u5c11\u7684\u60c5\u51b5\u3002\u5982\u679c\u6587\u4ef6\u975e\u5e38\u5927\uff0c\u53ef\u80fd\u4f1a\u5bfc\u81f4\u5185\u5b58\u5360\u7528\u8fc7\u591a\u3002<\/p>\n<\/p>\n
\u4e8c\u3001\u4f7f\u7528deque\u8fdb\u884c\u9ad8\u6548\u9006\u5e8f<\/h2>\n<\/p>\n
\u5bf9\u4e8e\u5927\u6587\u4ef6\uff0c\u4f7f\u7528deque\uff08\u53cc\u7aef\u961f\u5217\uff09\u662f\u4e00\u4e2a\u66f4\u9ad8\u6548\u7684\u9009\u62e9\uff0c\u56e0\u4e3a\u5b83\u53ef\u4ee5\u5728\u4e0d\u5360\u7528\u5927\u91cf\u5185\u5b58\u7684\u60c5\u51b5\u4e0b\u5b9e\u73b0\u9006\u5e8f\u8bfb\u53d6\u3002<\/p>\n<\/p>\n
1. \u5bfc\u5165collections\u6a21\u5757<\/h3>\n<\/p>\n
from collections import deque<\/p>\n
<\/code><\/pre>\n<\/p>\n
2. \u8bfb\u53d6\u6587\u4ef6\u5e76\u9006\u5e8f<\/h3>\n<\/p>\n
with open('example.txt', 'r') as file:<\/p>\n
    d = deque(file, maxlen=0)<\/p>\n
    for line in reversed(d):<\/p>\n
        print(line.strip())<\/p>\n
<\/code><\/pre>\n<\/p>\n
deque\u7684maxlen\u53c2\u6570\u8bbe\u7f6e\u4e3a0\uff0c\u8868\u793a\u4e0d\u9650\u5236\u961f\u5217\u957f\u5ea6\u3002deque\u5728\u5185\u5b58\u4f7f\u7528\u65b9\u9762\u66f4\u52a0\u9ad8\u6548\uff0c\u9002\u5408\u5904\u7406\u5927\u6587\u4ef6\u3002<\/p>\n<\/p>\n
\u4e09\u3001\u4f7f\u7528\u5806\u6808\uff08\u5217\u8868\uff09\u8fdb\u884c\u9006\u5e8f<\/h2>\n<\/p>\n
\u5806\u6808\u662f\u4e00\u79cd\u540e\u8fdb\u5148\u51fa\u7684\u6570\u636e\u7ed3\u6784\uff0c\u4f7f\u7528\u5217\u8868\u6a21\u62df\u5806\u6808\u4e5f\u662f\u4e00\u79cd\u53ef\u884c\u7684\u65b9\u6cd5\u3002<\/p>\n<\/p>\n
1. \u8bfb\u53d6\u6587\u4ef6\u5e76\u5b58\u5165\u5806\u6808<\/h3>\n<\/p>\n
stack = []<\/p>\n
with open('example.txt', 'r') as file:<\/p>\n
    for line in file:<\/p>\n
        stack.append(line)<\/p>\n
<\/code><\/pre>\n<\/p>\n
2. \u5f39\u51fa\u5e76\u6253\u5370\u5806\u6808\u4e2d\u7684\u5143\u7d20<\/h3>\n<\/p>\n
while stack:<\/p>\n
    print(stack.pop().strip())<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u901a\u8fc7\u5217\u8868\u7684append()\u548cpop()\u65b9\u6cd5\u6765\u6a21\u62df\u5806\u6808\u64cd\u4f5c\uff0c\u540c\u6837\u9002\u7528\u4e8e\u6587\u4ef6\u8f83\u5c0f\u7684\u60c5\u51b5\u3002<\/p>\n<\/p>\n
\u56db\u3001\u4f7f\u7528\u4e34\u65f6\u6587\u4ef6\u8fdb\u884c\u9006\u5e8f<\/h2>\n<\/p>\n
\u5bf9\u4e8e\u5185\u5b58\u4f7f\u7528\u975e\u5e38\u654f\u611f\u7684\u573a\u666f\uff0c\u53ef\u4ee5\u5c06\u6587\u4ef6\u5185\u5bb9\u5199\u5165\u4e34\u65f6\u6587\u4ef6\u5e76\u9006\u5e8f\u8bfb\u53d6\u3002<\/p>\n<\/p>\n
1. \u8bfb\u53d6\u6587\u4ef6\u5185\u5bb9\u5e76\u5199\u5165\u4e34\u65f6\u6587\u4ef6<\/h3>\n<\/p>\n
import tempfile<\/p>\n
with open('example.txt', 'r') as file, tempfile.TemporaryFile('w+t') as temp_file:<\/p>\n
    for line in file:<\/p>\n
        temp_file.write(line)<\/p>\n
    temp_file.seek(0)<\/p>\n
<\/code><\/pre>\n<\/p>\n
2. \u9006\u5e8f\u8bfb\u53d6\u4e34\u65f6\u6587\u4ef6<\/h3>\n<\/p>\n
with tempfile.TemporaryFile('r') as temp_file:<\/p>\n
    lines = temp_file.readlines()<\/p>\n
    for line in reversed(lines):<\/p>\n
        print(line.strip())<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u901a\u8fc7\u4f7f\u7528\u4e34\u65f6\u6587\u4ef6\uff0c\u907f\u514d\u4e86\u5c06\u6574\u4e2a\u6587\u4ef6\u5185\u5bb9\u52a0\u8f7d\u5230\u5185\u5b58\u4e2d\uff0c\u9002\u5408\u8d85\u5927\u6587\u4ef6\u3002<\/p>\n<\/p>\n
\u4e94\u3001\u4f7f\u7528\u5185\u5b58\u6620\u5c04\u6587\u4ef6\uff08mmap\uff09<\/h2>\n<\/p>\n
\u5185\u5b58\u6620\u5c04\u6587\u4ef6\uff08mmap\uff09\u53ef\u4ee5\u5c06\u6587\u4ef6\u5185\u5bb9\u6620\u5c04\u5230\u5185\u5b58\u4e2d\uff0c\u63d0\u4f9b\u9ad8\u6548\u7684\u6587\u4ef6\u8bfb\u53d6\u65b9\u5f0f\u3002<\/p>\n<\/p>\n
1. \u5bfc\u5165mmap\u6a21\u5757<\/h3>\n<\/p>\n
import mmap<\/p>\n
<\/code><\/pre>\n<\/p>\n
2. \u8bfb\u53d6\u5e76\u9006\u5e8f\u6587\u4ef6\u5185\u5bb9<\/h3>\n<\/p>\n
with open('example.txt', 'r+') as file:<\/p>\n
    mmapped_file = mmap.mmap(file.fileno(), 0)<\/p>\n
    lines = mmapped_file.read().splitlines()<\/p>\n
    for line in reversed(lines):<\/p>\n
        print(line.decode('utf-8').strip())<\/p>\n
<\/code><\/pre>\n<\/p>\n
\u8fd9\u79cd\u65b9\u6cd5\u5bf9\u4e8e\u5927\u578b\u6587\u4ef6\u4e5f\u975e\u5e38\u9ad8\u6548\uff0c\u4f46\u9700\u8981\u6ce8\u610f\u5185\u5b58\u6620\u5c04\u6587\u4ef6\u7684\u517c\u5bb9\u6027\u3002<\/p>\n<\/p>\n
\u516d\u3001\u603b\u7ed3<\/h2>\n<\/p>\n
\u6309\u884c\u9006\u5e8f\u8bfb\u53d6\u6587\u4ef6<\/strong>\u5728Python\u4e2d\u6709\u591a\u79cd\u5b9e\u73b0\u65b9\u5f0f\uff0c\u9009\u62e9\u5408\u9002\u7684\u65b9\u6cd5\u9700\u8981\u6839\u636e\u6587\u4ef6\u5927\u5c0f\u548c\u5185\u5b58\u4f7f\u7528\u60c5\u51b5\u6765\u51b3\u5b9a\u3002\u4f7f\u7528readlines()\u65b9\u6cd5\u548creversed()\u51fd\u6570<\/strong>\u662f\u6700\u7b80\u5355\u76f4\u63a5\u7684\u65b9\u5f0f\uff0c\u9002\u7528\u4e8e\u5c0f\u578b\u6587\u4ef6\uff1b\u4f7f\u7528deque<\/strong>\u548cmmap<\/strong>\u5219\u9002\u7528\u4e8e\u5927\u578b\u6587\u4ef6\u6216\u5185\u5b58\u654f\u611f\u7684\u573a\u666f\uff1b\u4f7f\u7528\u5806\u6808\u548c\u4e34\u65f6\u6587\u4ef6<\/strong>\u65b9\u6cd5\u63d0\u4f9b\u4e86\u66f4\u591a\u7684\u7075\u6d3b\u6027\u548c\u5185\u5b58\u4f18\u5316\u9009\u9879\u3002<\/p>\n<\/p>\n
\u901a\u8fc7\u4ee5\u4e0a\u65b9\u6cd5\u7684\u8be6\u7ec6\u4ecb\u7ecd\u548c\u4ee3\u7801\u793a\u4f8b\uff0c\u76f8\u4fe1\u4f60\u80fd\u591f\u6839\u636e\u5b9e\u9645\u9700\u6c42\u9009\u62e9\u6700\u5408\u9002\u7684\u65b9\u6848\u6765\u6309\u884c\u9006\u5e8f\u8bfb\u53d6\u6587\u4ef6\u3002<\/p>\n<\/p>\n
\u76f8\u5173\u95ee\u7b54FAQs\uff1a<\/strong><\/h2>\n
 \u5982\u4f55\u5728Python\u4e2d\u5b9e\u73b0\u6587\u4ef6\u7684\u9006\u5e8f\u8bfb\u53d6\uff1f<\/strong>
\u5728Python\u4e2d\uff0c\u53ef\u4ee5\u4f7f\u7528\u5185\u7f6e\u7684\u6587\u4ef6\u64cd\u4f5c\u65b9\u6cd5\u7ed3\u5408reversed()<\/code>\u51fd\u6570\u6765\u5b9e\u73b0\u6587\u4ef6\u7684\u9006\u5e8f\u8bfb\u53d6\u3002\u9996\u5148\u6253\u5f00\u6587\u4ef6\u5e76\u8bfb\u53d6\u6240\u6709\u884c\uff0c\u7136\u540e\u4f7f\u7528reversed()<\/code>\u51fd\u6570\u5bf9\u884c\u8fdb\u884c\u53cd\u8f6c\uff0c\u6700\u540e\u9010\u884c\u8f93\u51fa\u6216\u5904\u7406\u6570\u636e\u3002\u8fd9\u79cd\u65b9\u6cd5\u7b80\u5355\u800c\u9ad8\u6548\uff0c\u975e\u5e38\u9002\u5408\u9700\u8981\u6309\u884c\u9006\u5e8f\u5904\u7406\u6587\u672c\u6587\u4ef6\u7684\u573a\u666f\u3002<\/p>\n
\u662f\u5426\u53ef\u4ee5\u4f7f\u7528\u5185\u5b58\u4e2d\u7684\u6570\u636e\u7ed3\u6784\u6765\u53cd\u8f6c\u6587\u4ef6\u884c\uff1f<\/strong>
\u5f53\u7136\u53ef\u4ee5\u3002\u5728\u8bfb\u53d6\u6587\u4ef6\u7684\u8fc7\u7a0b\u4e2d\uff0c\u53ef\u4ee5\u5c06\u6240\u6709\u884c\u5b58\u50a8\u5728\u4e00\u4e2a\u5217\u8868\u4e2d\u3002\u5229\u7528\u5217\u8868\u7684\u5207\u7247\u529f\u80fd\uff0c\u53ef\u4ee5\u975e\u5e38\u65b9\u4fbf\u5730\u5b9e\u73b0\u9006\u5e8f\u3002\u793a\u4f8b\u4ee3\u7801\u5982\u4e0b\uff1a  <\/p>\n
with open('example.txt', 'r') as file:\n    lines = file.readlines()\n    for line in lines[::-1]:\n        print(line.strip())\n<\/code><\/pre>\n
\u8fd9\u79cd\u65b9\u6cd5\u5728\u5904\u7406\u5c0f\u578b\u6587\u4ef6\u65f6\u975e\u5e38\u6709\u6548\uff0c\u4f46\u5bf9\u4e8e\u975e\u5e38\u5927\u7684\u6587\u4ef6\uff0c\u53ef\u80fd\u4f1a\u5360\u7528\u8f83\u591a\u5185\u5b58\u3002<\/p>\n
\u5982\u679c\u6587\u4ef6\u975e\u5e38\u5927\uff0c\u5982\u4f55\u6709\u6548\u5730\u6309\u884c\u9006\u5e8f\u8bfb\u53d6\uff1f<\/strong>
\u5bf9\u4e8e\u5927\u6587\u4ef6\uff0c\u53ef\u4ee5\u8003\u8651\u4f7f\u7528deque<\/code>\u7c7b\uff0c\u5b83\u5141\u8bb8\u4ece\u4e24\u7aef\u9ad8\u6548\u5730\u6dfb\u52a0\u548c\u5220\u9664\u5143\u7d20\u3002\u901a\u8fc7\u8bbe\u7f6e\u4e00\u4e2a\u56fa\u5b9a\u957f\u5ea6\u7684deque<\/code>\uff0c\u53ef\u4ee5\u5728\u904d\u5386\u6587\u4ef6\u65f6\u4fdd\u6301\u6700\u65b0\u7684\u884c\uff0c\u800c\u4e0d\u9700\u8981\u5c06\u6574\u4e2a\u6587\u4ef6\u52a0\u8f7d\u5230\u5185\u5b58\u4e2d\u3002\u4ee5\u4e0b\u662f\u4e00\u4e2a\u793a\u4f8b\uff1a  <\/p>\n
from collections import deque\n\nwith open('large_file.txt', 'r') as file:\n    d = deque(maxlen=100)  # \u53ef\u4ee5\u6839\u636e\u9700\u8981\u8c03\u6574\u6700\u5927\u957f\u5ea6\n    for line in file:\n        d.append(line.strip())\n    for line in reversed(d):\n        print(line)\n<\/code><\/pre>\n
\u8fd9\u79cd\u65b9\u6cd5\u9002\u5408\u4e8e\u9700\u8981\u5904\u7406\u5927\u6587\u4ef6\u7684\u60c5\u51b5\uff0c\u65e2\u8282\u7701\u5185\u5b58\u53c8\u80fd\u5b9e\u73b0\u6309\u884c\u9006\u5e8f\u8bfb\u53d6\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"\u5728Python\u4e2d\uff0c\u6309\u884c\u9006\u5e8f\u8bfb\u53d6\u6587\u4ef6\u7684\u5e38\u7528\u65b9\u6cd5\u5305\u62ec\u4f7f\u7528readlines()\u65b9\u6cd5\u8bfb\u53d6\u6587\u4ef6\u3001\u4f7f\u7528reversed( […]","protected":false},"author":3,"featured_media":1090804,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37],"tags":[],"acf":[],"_links":{"self":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1090794"}],"collection":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/comments?post=1090794"}],"version-history":[{"count":"1","href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1090794\/revisions"}],"predecessor-version":[{"id":1090807,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/posts\/1090794\/revisions\/1090807"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media\/1090804"}],"wp:attachment":[{"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/media?parent=1090794"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/categories?post=1090794"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/docs.pingcode.com\/wp-json\/wp\/v2\/tags?post=1090794"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}