{"id":1635,"date":"2020-06-21T21:00:55","date_gmt":"2020-06-21T13:00:55","guid":{"rendered":"http:\/\/39.97.231.10\/?p=1635"},"modified":"2020-06-21T21:00:55","modified_gmt":"2020-06-21T13:00:55","slug":"python-%e7%9a%84-datetime-%e6%a8%a1%e5%9d%97","status":"publish","type":"post","link":"http:\/\/www.weijing.co\/?p=1635","title":{"rendered":"Python \u7684 datetime \u6a21\u5757"},"content":{"rendered":"
\nPython \u7684 datetime \u6a21\u5757\u53ef\u4ee5\u81ea\u5b9a\u4e49\u65e5\u671f\u7684\u663e\u793a\u683c\u5f0f\uff0c\u800c\u4e14\u8fd8\u53ef\u4ee5\u5f88\u65b9\u4fbf\u5730\u5bf9\u65e5\u671f\u8fdb\u884c\u7b97\u672f\u8fd0\u7b97\uff0c\u6bd4\u5982\u589e\u51cf\u5929\u6570\u7b49\u64cd\u4f5c\u3002
\ndatetime \u6a21\u5757\u5b9a\u4e49\u4e86 datetime \u6570\u636e\u7c7b\u578b\uff0c\u7528\u4e8e\u8868\u793a\u4e00\u4e2a\u7279\u5b9a\u7684\u65f6\u523b\u3002<\/p>\n
\n
import datetime\nimport logging\nimport time\nlogging.basicConfig(level=logging.DEBUG, format=\\'%(levelname)s - %(message)s\\')\n\\'\\'\\'\ndatetime \u6a21\u5757\n@author Deniro Lee\n\\'\\'\\'\ndt = datetime.datetime(2020, 10, 21, 17, 32, 34)\nlogging.info(\\'%s-%s-%s %s:%s:%s\\', dt.year, dt.month, dt.day, dt.hour, dt.minute, dt.second)\n<\/pre>\n<\/div>\n
\u8fd0\u884c\u7ed3\u679c\uff1a<\/p>\n
\n
INFO - 2020-10-21 17:32:34\n<\/pre>\n<\/div>\n
1 \u8f6c\u6362 Unix \u7eaa\u5143\u65f6\u95f4\u6233<\/h2>\n
Unix \u7eaa\u5143\u65f6\u95f4\u6233\u53ef\u4ee5\u901a\u8fc7 datetime.datetime.fromtimestamp() \uff0c\u8f6c\u6362\u4e3a datetime \u5bf9\u8c61\u3002 datetime \u5bf9\u8c61\u7684\u65e5\u671f\u548c\u65f6\u95f4\u4f1a\u6839\u636e\u672c\u5730\u65f6\u533a\u81ea\u52a8\u8f6c\u6362\u3002<\/p>\n
\n
dt = datetime.datetime.fromtimestamp(10000000)\nlogging.info(\\'from 10000000 -> %s\\', dt)\ndt = datetime.datetime.fromtimestamp(time.time())\nlogging.info(\\'from now -> %s\\', dt)\n<\/pre>\n<\/div>\n
\u8fd0\u884c\u7ed3\u679c\uff1a<\/p>\n
\n
INFO - from 10000000 -> 1970-04-27 01:46:40\nINFO - from now -> 2020-01-19 10:23:14.695018\n<\/pre>\n<\/div>\n
2 \u6bd4\u8f83\u65f6\u95f4<\/h2>\n
datetime \u5bf9\u8c61\u53ef\u4ee5\u7528\u6bd4\u8f83\u64cd\u4f5c\u7b26\u8fdb\u884c\u65f6\u95f4\u6bd4\u8f83\u3002<\/p>\n
\n
new_year_2019 = datetime.datetime(2019, 1, 1, 0, 0, 0)\nnew_year_2020 = datetime.datetime(2020, 1, 1, 0, 0, 0)\nlogging.info(\\'2019 > 2020 -> %s\\', new_year_2019 > new_year_2020)\nlogging.info(\\'2019 < 2020 -> %s\\', new_year_2019 < new_year_2020)\nlogging.info(\\'2019 != 2020 -> %s\\', new_year_2019 != new_year_2020)\n<\/pre>\n<\/div>\n
\u8fd0\u884c\u7ed3\u679c\uff1a<\/p>\n
\n
INFO - 2019 > 2020 -> False\nINFO - 2019 < 2020 -> True\nINFO - 2019 != 2020 -> True\n<\/pre>\n<\/div>\n
\u5229\u7528\u6bd4\u8f83\u65f6\u95f4\u65b9\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u5b9e\u73b0\u4e00\u4e2a\u8ba1\u5212\u4efb\u52a1\uff0c\u6bd4\u5982\u7a0b\u5e8f\u5230\u67d0\u4e00\u65f6\u523b\u65f6\uff0c\u624d\u5f00\u59cb\u6267\u884c\u4e1a\u52a1\u903b\u8f91\u3002<\/p>\n
\n
dt = datetime.datetime(2020, 10, 21, 17, 32, 34)\nwhile datetime.datetime.now() < dt:\n    time.sleep(1)\n    logging.info(\\'sleep ...\\')\n<\/pre>\n<\/div>\n
\u8fd0\u884c\u7ed3\u679c\uff1a<\/p>\n
\n
INFO - sleep ...\nINFO - sleep ...\nINFO - sleep ...\n<\/pre>\n<\/div>\n
\u8fd9\u91cc\u5229\u7528\u4e86\u4e00\u4e2a while \u5faa\u73af\uff0c\u8ba9\u7a0b\u5e8f\u76f4\u5230\u67d0\u4e00\u4e2a\u7279\u5b9a\u7684\u65f6\u95f4\u5230\u6765\u4e4b\u524d\uff0c\u4e00\u76f4\u5904\u4e8e\u4f11\u7720\u72b6\u6001\u3002<\/p>\n
3 timedelta \u6570\u636e\u7c7b\u578b<\/h2>\n
datetime \u6a21\u5757\u8fd8\u5b9a\u4e49\u4e86 timedelta \u6570\u636e\u7c7b\u578b\uff0c\u5b83\u8868\u793a\u7684\u662f\u4e00\u6bb5\u65f6\u95f4\u3002<\/p>\n
\n
delta = datetime.timedelta(days=12, hours=8, minutes=36, seconds=58)\nlogging.info(\\'delta.days -> %s,delta.seconds -> %s,delta.microseconds -> %s\\', delta.days, delta.seconds,\n             delta.microseconds)\nlogging.info(\\'total_seconds -> %s\\', delta.total_seconds())\nlogging.info(\\'delta -> %s\\', delta)\n<\/pre>\n<\/div>\n
\u8fd0\u884c\u7ed3\u679c\uff1a<\/p>\n
\n
INFO - delta.days -> 12,delta.seconds -> 31018,delta.microseconds -> 0\nINFO - total_seconds -> 1067818.0\nINFO - delta -> 12 days, 8:36:58\n<\/pre>\n<\/div>\n
\u4f7f\u7528 datetime.timedelta()\u51fd\u6570\u6765\u521b\u5efa timedelta \u5bf9\u8c61\uff0c\u5b83\u63a5\u53d7\u5173\u952e\u5b57\u53c2\u6570 weeks\u3001 days\u3001 hours\u3001 minutes\u3001 seconds\u3001 milliseconds \u548c microseconds\u3002\u6ce8\u610f\uff1a \u8fd9\u91cc\u6ca1\u6709 month \u548c year \u5173\u952e\u5b57\u53c2\u6570\uff0c\u56e0\u4e3a\u201c\u6708\u201d\u548c\u201c\u5e74\u201d\u53ef\u4ee5\u901a\u8fc7\u5176\u5b83\u5173\u952e\u5b57\u53c2\u6570\u63a8\u7b97\u51fa\u6765\u3002
\ntimedelta \u5bf9\u8c61\u62e5\u6709\u7684\u603b\u65f6\u95f4\u4ee5\u5929 \u3001 \u79d2 \u3001 \u5fae\u79d2\u6765\u8868\u793a\u3002\u8fd9\u4e9b\u503c\u5206\u522b\u4fdd\u5b58\u5728 days \u3001 seconds\u548c microseconds \u5c5e\u6027\u4e2d \u3002total_seconds() \u65b9\u6cd5\u4f1a\u8fd4\u56de\u4ee5\u79d2\u8868\u793a\u7684\u65f6\u957f\u3002\u628a\u4e00\u4e2a timedelta \u5bf9\u8c61\u4f20\u5165 str() \uff0c\u5c31\u4f1a\u8fd4\u56de\u683c\u5f0f\u826f\u597d\u7684 \u3001 \u53ef\u4f9b\u4eba\u9605\u8bfb\u7684\u5b57\u7b26\u4e32\u8868\u793a\u5f62\u5f0f\u3002<\/p>\n
4 \u65f6\u95f4\u8fd0\u7b97<\/h2>\n
\u53ef\u4ee5\u4f7f\u7528\u7b97\u672f\u8fd0\u7b97\u7b26\u5bf9 datetime \u503c\u8fdb\u884c\u8fd0\u7b97\u3002<\/p>\n
\n
dt = datetime.datetime(2020, 10, 21, 17, 32, 34)\nlogging.info(\\'current time -> %s\\', dt)\ndays_30 = datetime.timedelta(days=30)\nlogging.info(\\'after 30 days -> %s\\', dt + days_30)\n<\/pre>\n<\/div>\n
\u8fd0\u884c\u7ed3\u679c\uff1a<\/p>\n
\n
INFO - delta.days -> 12,delta.seconds -> 31018,delta.microseconds -> 0\nINFO - total_seconds -> 1067818.0\nINFO - delta -> 12 days, 8:36:58\n<\/pre>\n<\/div>\n
\u5229\u7528+\u548c-\u8fd0\u7b97\u7b26\uff0c\u6211\u4eec\u53ef\u4ee5\u628a timedelta \u5bf9\u8c61\u4e0e datetime \u5bf9\u8c61\u6216\u5176\u4ed6 timedelta \u5bf9\u8c61\u8fdb\u884c\u76f8\u52a0\u6216\u76f8\u51cf\u3002timedelta \u5bf9\u8c61\u8fd8\u652f\u6301\u4e58\u3001\u9664\u8fd0\u7b97\u3002<\/p>\n
\n
dt = datetime.datetime(2020, 10, 21, 17, 32, 34)\ndays_150 = datetime.timedelta(days=30 * 5)\nlogging.info(\\'after 150 days -> %s\\', days_150)\nlogging.info(\\'dt-days_150 -> %s\\', dt - days_150)\nlogging.info(\\'dt-days_150 * 2 -> %s\\', dt - days_150 * 2)\n<\/pre>\n<\/div>\n
\u8fd0\u884c\u7ed3\u679c\uff1a<\/p>\n
\n
INFO - after 150 days -> 150 days, 0:00:00\nINFO - dt-days_150 -> 2020-05-24 17:32:34\nINFO - dt-days_150 * 2 -> 2019-12-26 17:32:34\n<\/pre>\n<\/div>\n
5 datetime \u5bf9\u8c61\u4e0e\u5b57\u7b26\u4e32\u4e4b\u95f4\u76f8\u4e92\u8f6c\u6362<\/h2>\n
\u5229\u7528 strftime() \u65b9\u6cd5\uff0c\u6211\u4eec\u53ef\u4ee5\u5c06 datetime \u5bf9\u8c61\u8f6c\u6362\u4e3a\u66f4\u53ef\u8bfb\u7684\u5b57\u7b26\u4e32\u3002 str ftime() \u51fd\u6570\u540d\u4e2d\u7684 f \u8868\u793a format\u3002
\nstrftime() \u65b9\u6cd5\u652f\u6301\u4ee5\u4e0b\u683c\u5f0f\u5316\u6307\u4ee4\uff1a<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
\u683c\u5f0f\u5316\u6307\u4ee4<\/th>\n\u542b\u4e49<\/th>\n<\/tr>\n<\/thead>\n
%Y<\/td>\n\u5e26\u4e16\u7eaa\u7684\u5e74\u4efd\uff0c\u4f8b\u5982\\’2020\\’<\/td>\n<\/tr>\n
%y<\/td>\n\u4e0d\u5e26\u4e16\u7eaa\u7684\u5e74\u4efd\uff0c \\’00\\’\u81f3\\’99\\’\uff081970 \u81f3 2069\uff09<\/td>\n<\/tr>\n
%m<\/td>\n\u6570\u5b57\u8868\u793a\u7684\u6708\u4efd, \\’01\\’\u81f3\\’12\\’<\/td>\n<\/tr>\n
%B<\/td>\n\u5b8c\u6574\u7684\u6708\u4efd\uff0c\u4f8b\u5982\\’November\\’<\/td>\n<\/tr>\n
%b<\/td>\n\u7b80\u5199\u7684\u6708\u4efd\uff0c\u4f8b\u5982\\’Nov\\’<\/td>\n<\/tr>\n
%d<\/td>\n\u4e00\u6708\u4e2d\u7684\u7b2c\u51e0\u5929\uff0c \\’01\\’\u81f3\\’31\\’<\/td>\n<\/tr>\n
%j<\/td>\n\u4e00\u5e74\u4e2d\u7684\u7b2c\u51e0\u5929\uff0c \\’001\\’\u81f3\\’366\\’<\/td>\n<\/tr>\n
%w<\/td>\n\u4e00\u5468\u4e2d\u7684\u7b2c\u51e0\u5929\uff0c \\’0\\’\uff08\u5468\u65e5\uff09\u81f3\\’6\\’\uff08\u5468\u516d\uff09<\/td>\n<\/tr>\n
%A<\/td>\n\u5b8c\u6574\u7684\u5468\u51e0\uff0c\u4f8b\u5982\\’Monday\\’<\/td>\n<\/tr>\n
%a<\/td>\n\u7b80\u5199\u7684\u5468\u51e0\uff0c\u4f8b\u5982\\’Mon\\’<\/td>\n<\/tr>\n
%H<\/td>\n\u5c0f\u65f6\uff0824 \u5c0f\u65f6\u65f6\u949f\uff09\uff0c \\’00\\’\u81f3\\’23\\’<\/td>\n<\/tr>\n
%I<\/td>\n\u5c0f\u65f6\uff0812 \u5c0f\u65f6\u65f6\u949f\uff09\uff0c \\’01\\’\u81f3\\’12\\’<\/td>\n<\/tr>\n
%M<\/td>\n\u5206\uff0c \\’00\\’\u81f3\\’59\\’<\/td>\n<\/tr>\n
%S<\/td>\n\u79d2\uff0c \\’00\\’\u81f3\\’59\\’<\/td>\n<\/tr>\n
%p<\/td>\n\\’AM\\’\u6216\\’PM\\’<\/td>\n<\/tr>\n
%%<\/td>\n\u8f6c\u4e49\u51fa\\’%\\’\u5b57\u7b26<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\u5411 strftime() \u65b9\u6cd5\u4f20\u5165\u4e00\u4e2a\u81ea\u5b9a\u4e49\u7684\u683c\u5f0f\u5b57\u7b26\u4e32\uff0c\u5176\u4e2d\u5305\u542b\u683c\u5f0f\u5316\u6307\u4ee4\uff0c strftime() \u5c31\u4f1a\u8fd4\u56de\u76f8\u5e94\u683c\u5f0f\u7684\u5b57\u7b26\u4e32\u3002
\n\u5982\u679c\u8981\u5c06\u5b57\u7b26\u4e32\u8f6c\u6362\u6210 datetime \u5bf9\u8c61\uff0c\u5c31\u662f\u7528\u53cd\u5411\u64cd\u4f5c\u65b9\u6cd5 strptime()\uff0c\u5b83\u6240\u652f\u6301\u7684\u683c\u5f0f\u5316\u6307\u4ee4\u4e0e strftime() \u65b9\u6cd5\u76f8\u540c\u3002<\/p>\n
\u6ce8\u610f\uff1a strptime() \u7684\u7b2c\u4e00\u4e2a\u5165\u53c2\u662f\u5e26\u6709\u65e5\u671f\u4fe1\u606f\u7684\u5b57\u7b26\u4e32\uff0c\u5b83\u5fc5\u987b\u51c6\u786e\u5339\u914d\u5b9a\u5236\u7684\u683c\u5f0f\u5b57\u7b26\u4e32\uff0c\u5426\u5219 Python \u4f1a\u629b\u51fa ValueError \u5f02\u5e38\u3002<\/p><\/blockquote>\n