{"id":204951,"date":"2025-05-29T08:36:36","date_gmt":"2025-05-29T00:36:36","guid":{"rendered":"https:\/\/server.hk\/cnblog\/204951\/"},"modified":"2025-05-29T08:36:36","modified_gmt":"2025-05-29T00:36:36","slug":"%e4%b8%8a%e4%b8%8b%e6%96%87%e7%ae%a1%e7%90%86%e5%99%a8%e6%8f%ad%e7%a7%98%ef%bc%9a%e7%ae%80%e5%8c%96-python-%e4%b8%ad%e7%9a%84%e8%b5%84%e6%ba%90%e5%a4%84%e7%90%86","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/204951\/","title":{"rendered":"\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u63ed\u79d8\uff1a\u7b80\u5316 Python \u4e2d\u7684\u8d44\u6e90\u5904\u7406"},"content":{"rendered":"<p><b><\/b>     <\/p>\n<h1>\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u63ed\u79d8\uff1a\u7b80\u5316 Python \u4e2d\u7684\u8d44\u6e90\u5904\u7406<\/h1>\n<p>\u4ece\u73b0\u5728\u5f00\u59cb\uff0c\u52aa\u529b\u5b66\u4e60\u5427\uff01\u672c\u6587<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\">\u300a\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u63ed\u79d8\uff1a\u7b80\u5316 Python \u4e2d\u7684\u8d44\u6e90\u5904\u7406\u300b<\/span>\u4e3b\u8981\u8bb2\u89e3\u4e86<span style=\"color: #FF6600;, Helvetica, Arial, sans-serif;font-size: 14px;background-color: #FFFFFF\"><\/span>\u7b49\u7b49\u76f8\u5173\u77e5\u8bc6\u70b9\uff0c\u6211\u4f1a\u5728\u4e2d\u6301\u7eed\u66f4\u65b0\u76f8\u5173\u7684\u7cfb\u5217\u6587\u7ae0\uff0c\u6b22\u8fce\u5927\u5bb6\u5173\u6ce8\u5e76\u79ef\u6781\u7559\u8a00\u5efa\u8bae\u3002\u4e0b\u9762\u5c31\u5148\u4e00\u8d77\u6765\u770b\u4e00\u4e0b\u672c\u7bc7\u6b63\u6587\u5185\u5bb9\u5427\uff0c\u5e0c\u671b\u80fd\u5e2e\u5230\u4f60\uff01<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.17golang.com\/uploads\/20241120\/1732064984673d36d864e05.jpg\" class=\"aligncenter\"><\/p>\n<p>python \u4e2d\u7684\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u662f\u4e00\u4e2a\u5f3a\u5927\u7684\u5de5\u5177\uff0c\u53ef\u8ba9\u60a8\u4ee5\u5b89\u5168\u6709\u6548\u7684\u65b9\u5f0f\u7ba1\u7406\u8d44\u6e90\u7684\u8bbe\u7f6e\u548c\u62c6\u5378\u3002\u5b83\u4eec\u63d0\u4f9b\u4e86\u4e00\u79cd\u65b9\u6cd5\u6765\u786e\u4fdd\u8d44\u6e90\u6b63\u786e\u521d\u59cb\u5316\u3001\u4f7f\u7528\u548c\u6e05\u7406\uff0c\u5373\u4f7f\u9762\u5bf9\u5f02\u5e38\u6216\u610f\u5916\u7684\u63a7\u5236\u6d41\u4e5f\u662f\u5982\u6b64\u3002<\/p>\n<p>\u4f7f\u7528\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u7684\u4e3b\u8981\u597d\u5904\u662f\u5b83\u4eec\u53ef\u4ee5\u5e2e\u52a9\u60a8\u7f16\u5199\u66f4\u5065\u58ee\u3001\u53ef\u7ef4\u62a4\u7684 python \u4ee3\u7801\u3002\u901a\u8fc7\u5c01\u88c5\u8d44\u6e90\u7ba1\u7406\u903b\u8f91\uff0c\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u53ef\u4ee5\u66f4\u8f7b\u677e\u5730\u786e\u4fdd\u8d44\u6e90\u5f97\u5230\u6b63\u786e\u5904\u7406\uff0c\u4ece\u800c\u964d\u4f4e\u8d44\u6e90\u6cc4\u6f0f\u6216\u72b6\u6001\u4e0d\u4e00\u81f4\u7684\u98ce\u9669\u3002<\/p>\n<p>\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u7684\u4e00\u4e9b\u5e38\u89c1\u7528\u4f8b\u5305\u62ec\uff1a<\/p>\n<ul>\n<li>\u6587\u4ef6\u5904\u7406\uff08\u4f8b\u5982\uff0copen()\uff09<\/li>\n<li>\u6570\u636e\u5e93\u8fde\u63a5<\/li>\n<li>\u9501\u5b9a\u673a\u5236<\/li>\n<li>\u4e34\u65f6\u76ee\u5f55\u7ba1\u7406<\/li>\n<li>\u5206\u6790\u548c\u8ba1\u65f6\u4ee3\u7801\u6267\u884c<\/li>\n<\/ul>\n<p>\u5728 python \u4e2d\u4f7f\u7528\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u7684\u4e3b\u8981\u65b9\u6cd5\u662f\u4f7f\u7528 with \u8bed\u53e5\u3002 with \u8bed\u53e5\u63d0\u4f9b\u4e86\u4f7f\u7528\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u7684\u4fbf\u6377\u8bed\u6cd5\uff0c\u4f7f\u60a8\u53ef\u4ee5\u4e13\u6ce8\u4e8e\u4ee3\u7801\u7684\u6838\u5fc3\u903b\u8f91\uff0c\u800c\u4e0d\u7528\u62c5\u5fc3\u8d44\u6e90\u7ba1\u7406\u3002<\/p>\n<p>\u4ee5\u4e0b\u662f\u4f7f\u7528 with \u8bed\u53e5\u6253\u5f00\u6587\u4ef6\u7684\u793a\u4f8b\uff1a<\/p>\n<pre>with open('data.txt', 'r') as file:\n    content = file.read()\n    print(content)\n<\/pre>\n<p>\u5f53\u9000\u51fa with \u5757\u65f6\uff0c\u65e0\u8bba\u662f\u6b63\u5e38\u9000\u51fa\u8fd8\u662f\u7531\u4e8e\u5f02\u5e38\uff0c\u90fd\u4f1a\u81ea\u52a8\u8c03\u7528\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u7684 __exit__() \u65b9\u6cd5\uff0c\u786e\u4fdd\u6587\u4ef6\u6b63\u786e\u5173\u95ed\u3002<\/p>\n<p>\u8981\u521b\u5efa\u81ea\u5b9a\u4e49\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\uff0c\u60a8\u9700\u8981\u5b9a\u4e49\u4e00\u4e2a\u5177\u6709\u4e24\u4e2a\u7279\u6b8a\u65b9\u6cd5\u7684\u7c7b\uff1a__enter__() \u548c __exit__()\u3002 __enter__() \u65b9\u6cd5\u8d1f\u8d23\u8bbe\u7f6e\u8d44\u6e90\uff0c\u800c __exit__() \u65b9\u6cd5\u8d1f\u8d23\u6e05\u7406\u8d44\u6e90\u3002<\/p>\n<p>\u4ee5\u4e0b\u662f\u7ba1\u7406 postgresql \u6570\u636e\u5e93\u8fde\u63a5\u7684\u81ea\u5b9a\u4e49\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u7684\u793a\u4f8b\uff1a<\/p>\n<pre>import psycopg2\n\nclass postgresmanager:\n    def __init__(self, host, port, database, user, password):\n        self.host = host\n        self.port = port\n        self.database = database\n        self.user = user\n        self.password = password\n        self.conn = none\n\n    def __enter__(self):\n        self.conn = psycopg2.connect(\n            host=self.host,\n            port=self.port,\n            database=self.database,\n            user=self.user,\n            password=self.password\n        )\n        return self.conn\n\n    def __exit__(self, exc_type, exc_value, traceback):\n        if self.conn:\n            if exc_type is none:\n                self.conn.commit()\n            else:\n                self.conn.rollback()\n            self.conn.close()\n        return false\n<\/pre>\n<p>\u5728\u8fd9\u4e2a\u4f8b\u5b50\u4e2d\uff0c__enter__()\u65b9\u6cd5\u4f7f\u7528\u63d0\u4f9b\u7684\u8fde\u63a5\u53c2\u6570\u5efa\u7acb\u5230postgresql\u6570\u636e\u5e93\u7684\u8fde\u63a5\uff0c__exit__()\u65b9\u6cd5\u8d1f\u8d23\u63d0\u4ea4\u6216\u56de\u6eda\u4e8b\u52a1\uff0c\u5177\u4f53\u53d6\u51b3\u4e8e\u662f\u5426\u53d1\u751f\u5f02\u5e38\uff0c\u7136\u540e\u5173\u95ed\u8fde\u63a5\u3002<\/p>\n<p>__exit__() \u65b9\u6cd5\u63a5\u6536\u4e09\u4e2a\u53c2\u6570\uff1aexc_type\u3001exc_value \u548ctraceback\uff0c\u5b83\u4eec\u63d0\u4f9b\u6709\u5173 with \u5757\u4e2d\u53d1\u751f\u7684\u4efb\u4f55\u5f02\u5e38\u7684\u4fe1\u606f\u3002\u5728\u672c\u4f8b\u4e2d\uff0c\u5982\u679c\u53d1\u751f\u5f02\u5e38\uff0c\u8be5\u65b9\u6cd5\u5c06\u56de\u6eda\u4e8b\u52a1\uff1b\u5426\u5219\uff0c\u5b83\u4f1a\u63d0\u4ea4\u4e8b\u52a1\u3002<\/p>\n<p>\u901a\u8fc7\u4f7f\u7528\u6b64\u81ea\u5b9a\u4e49\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\uff0c\u60a8\u53ef\u4ee5\u7b80\u5316\u6570\u636e\u5e93\u4ea4\u4e92\u5e76\u786e\u4fdd\u8fde\u63a5\u6b63\u786e\u5173\u95ed\uff0c\u5373\u4f7f\u9762\u5bf9\u5f02\u5e38\u4e5f\u662f\u5982\u6b64\uff1a<\/p>\n<pre>with postgresmanager('localhost', 5432, 'demo_db', 'myuser', 'mypassword') as conn:\n    with conn.cursor() as cursor:\n        cursor.execute(\"create table customers (id serial primary key, name text)\")\n        cursor.execute(\"insert into customers (name) values (%s)\", ('meqdad',))\n        # other database operations here...\n<\/pre>\n<p>\u8fd9\u79cd\u65b9\u6cd5\u901a\u8fc7\u5c06\u6570\u636e\u5e93\u8fde\u63a5\u7ba1\u7406\u903b\u8f91\u5c01\u88c5\u5728\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u4e2d\uff0c\u5e2e\u52a9\u60a8\u7f16\u5199\u66f4\u5065\u58ee\u4e14\u53ef\u7ef4\u62a4\u7684\u4ee3\u7801\u3002<\/p>\n<p>\u9664\u4e86\u521b\u5efa\u81ea\u5b9a\u4e49\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u7c7b\u4e4b\u5916\uff0c\u60a8\u8fd8\u53ef\u4ee5\u4f7f\u7528\u751f\u6210\u5668\u51fd\u6570\u521b\u5efa\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u3002\u8fd9\u79cd\u65b9\u6cd5\u5728\u67d0\u4e9b\u60c5\u51b5\u4e0b\u53ef\u4ee5\u66f4\u7b80\u6d01\u3001\u66f4\u5bb9\u6613\u9605\u8bfb\u3002<\/p>\n<p>\u8fd9\u662f\u7ba1\u7406\u9501\u7684\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u751f\u6210\u5668\u7684\u793a\u4f8b\uff1a<\/p>\n<pre>from contextlib import contextmanager\nfrom threading import Lock\n\n@contextmanager\ndef lock_manager(lock):\n    lock.acquire()\n    try:\n        yield lock\n    finally:\n        lock.release()\n<\/pre>\n<p>\u5728\u6b64\u793a\u4f8b\u4e2d\uff0c@contextmanager \u88c5\u9970\u5668\u7528\u4e8e\u5b9a\u4e49\u5145\u5f53\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u7684\u751f\u6210\u5668\u51fd\u6570\u3002 yield \u8bed\u53e5\u7528\u4e8e\u5b9a\u4e49\u63a7\u5236\u6743\u8f6c\u79fb\u5230 with \u5757\u7684\u70b9\uff0cfinally \u5757\u786e\u4fdd\u5373\u4f7f\u53d1\u751f\u5f02\u5e38\u4e5f\u80fd\u91ca\u653e\u9501\u3002<\/p>\n<p>python \u6807\u51c6\u5e93\u63d0\u4f9b\u4e86\u8bb8\u591a\u5185\u7f6e\u7684\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\uff0c\u60a8\u53ef\u4ee5\u5728\u4ee3\u7801\u4e2d\u4f7f\u7528\u5b83\u4eec\u3002\u5176\u4e2d\u5305\u62ec\uff1a<\/p>\n<ul>\n<li> open()\uff1a\u7ba1\u7406\u6587\u4ef6\u7684\u6253\u5f00\u548c\u5173\u95ed\u3002<\/li>\n<li> lock()\uff1a\u7ba1\u7406\u9501\u7684\u83b7\u53d6\u548c\u91ca\u653e\u3002<\/li>\n<li> threadpoolexecutor()\uff1a\u7ba1\u7406\u5de5\u4f5c\u7ebf\u7a0b\u6c60\u7684\u521b\u5efa\u548c\u6e05\u7406\u3002<\/li>\n<\/ul>\n<p>\u4f7f\u7528\u8fd9\u4e9b\u5185\u7f6e\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u53ef\u4ee5\u5e2e\u52a9\u60a8\u7f16\u5199\u66f4\u7b80\u6d01\u3001\u66f4\u53ef\u9760\u7684\u4ee3\u7801\uff0c\u56e0\u4e3a\u8d44\u6e90\u7ba1\u7406\u903b\u8f91\u5df2\u7ecf\u4e3a\u60a8\u5b9e\u73b0\u3002<\/p>\n<p>\u4e0e\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u5408\u4f5c\u65f6\uff0c\u9700\u8981\u7262\u8bb0\u4e00\u4e9b\u6700\u4f73\u5b9e\u8df5\u548c\u6ce8\u610f\u4e8b\u9879\uff1a<\/p>\n<ul>\n<li> <strong>\u9519\u8bef\u5904\u7406\u548c\u6e05\u7406<\/strong>\uff1a\u786e\u4fdd\u60a8\u7684 __exit__() \u65b9\u6cd5\u6b63\u786e\u5904\u7406\u5f02\u5e38\u5e76\u6e05\u7406\u8d44\u6e90\uff0c\u5373\u4f7f\u9762\u5bf9\u610f\u5916\u9519\u8bef\u4e5f\u662f\u5982\u6b64\u3002<\/li>\n<li> <strong>\u5d4c\u5957\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668<\/strong>\uff1a\u60a8\u53ef\u4ee5\u76f8\u4e92\u5d4c\u5957\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\uff0c\u8fd9\u5728\u7ba1\u7406\u591a\u4e2a\u8d44\u6e90\u65f6\u975e\u5e38\u6709\u7528\u3002<\/li>\n<li> <strong>\u6027\u80fd\u6ce8\u610f\u4e8b\u9879<\/strong>\uff1a\u867d\u7136\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u901a\u5e38\u5f88\u9ad8\u6548\uff0c\u4f46\u8bf7\u6ce8\u610f\u8d44\u6e90\u7684\u8bbe\u7f6e\u548c\u62c6\u5378\u6240\u5e26\u6765\u7684\u4efb\u4f55\u5f00\u9500\uff0c\u5c24\u5176\u662f\u5728\u6027\u80fd\u5173\u952e\u7684\u4ee3\u7801\u4e2d\u3002<\/li>\n<\/ul>\n<p>\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u662f python \u751f\u6001\u7cfb\u7edf\u4e2d\u7684\u4e00\u4e2a\u5f3a\u5927\u5de5\u5177\uff0c\u5141\u8bb8\u60a8\u7f16\u5199\u66f4\u5065\u58ee\u3001\u53ef\u7ef4\u62a4\u7684 python \u4ee3\u7801\u3002 <\/p>\n<p>\u901a\u8fc7\u5c01\u88c5\u8d44\u6e90\u7ba1\u7406\u903b\u8f91\uff0c\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u5e2e\u52a9\u60a8\u786e\u4fdd\u8d44\u6e90\u5f97\u5230\u6b63\u786e\u5904\u7406\uff0c\u964d\u4f4e\u8d44\u6e90\u6cc4\u6f0f\u6216\u72b6\u6001\u4e0d\u4e00\u81f4\u7684\u98ce\u9669\u3002<\/p>\n<p>\u65e0\u8bba\u60a8\u662f\u4f7f\u7528\u5185\u7f6e\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u8fd8\u662f\u521b\u5efa\u81ea\u5df1\u7684\u81ea\u5b9a\u4e49\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\uff0c\u4e86\u89e3\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u7684\u57fa\u7840\u77e5\u8bc6\u90fd\u5c06\u5e2e\u52a9\u60a8\u7f16\u5199\u66f4\u6e05\u6670\u3001\u66f4\u9ad8\u6548\u3001\u66f4\u53ef\u9760\u7684 python \u4ee3\u7801\u3002<\/p>\n<p>\u597d\u4e86\uff0c\u672c\u6587\u5230\u6b64\u7ed3\u675f\uff0c\u5e26\u5927\u5bb6\u4e86\u89e3\u4e86\u300a\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u63ed\u79d8\uff1a\u7b80\u5316 Python \u4e2d\u7684\u8d44\u6e90\u5904\u7406\u300b\uff0c\u5e0c\u671b\u672c\u6587\u5bf9\u4f60\u6709\u6240\u5e2e\u52a9\uff01\u5173\u6ce8\u516c\u4f17\u53f7\uff0c\u7ed9\u5927\u5bb6\u5206\u4eab\u66f4\u591a\u6587\u7ae0\u77e5\u8bc6\uff01<\/p>\n<p>      \u7248\u672c\u58f0\u660e \u672c\u6587\u8f6c\u8f7d\u4e8e\uff1adev.to \u5982\u6709\u4fb5\u72af\uff0c\u8bf7\u8054\u7cfb\u5220\u9664<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e0a\u4e0b\u6587\u7ba1\u7406\u5668\u63ed\u79d8\uff1a\u7b80\u5316 Pyth&#46;&#46;&#46;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-204951","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/204951","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=204951"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/204951\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=204951"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=204951"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=204951"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}