python 获取毫秒级时间问题的解决

时间:2022-10-08 11:26:03

根据网上的一些说法,

在python里获取ms级系统时间可以通过以下方式获取:

?
1
2
import datetime
print(datetime.datetime.now().microsecond)

但通过以下代码测试,发现返回的并不是ms的值,而是us的值:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
import datetime
def getTime_ms():
    return (datetime.datetime.now().hour*3600 +\
            datetime.datetime.now().minute*60+\
            datetime.datetime.now().second )*1000+\
           datetime.datetime.now().microsecond/1000
 
def timetime():
    t = getTime_ms()
    while getTime_ms() - t < 500:
        pass
    a = getTime_ms()
    print(t, a, a- t)
  
if __name__ == '__main__':
    from timeit import timeit
    t = timeit('timetime()', 'from __main__ import timetime', number=1)
    print(t)

打印结果

(35460614, 35461114, 500) 0.499531984329

上面实验不太直观,换一个直观点的:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
def timetime():
    t1 = datetime.datetime.now()
    while 1:
        t2 = datetime.datetime.now()
        if (t2 - t1).microseconds >= 1:
            print(t2,t2.microsecond,t1,t1.microsecond,(t2-t1).seconds)
            break
 
if __name__ == '__main__':
    from timeit import timeit
    t = timeit('timetime()', 'from __main__ import timetime', number=1)
    print(t)
    #print (datetime.datetime.now())

输出

(datetime.datetime(2019, 4, 3, 10, 6, 20, 461882), 461882, datetime.datetime(2019, 4, 3, 10, 6, 20, 461863), 461863, 0) 7.10487365723e-05

?
1
2
3
4
5
6
7
8
9
10
11
12
13
def timetime():
    t1 = datetime.datetime.now()
    while 1:
        t2 = datetime.datetime.now()
        if (t2 - t1).microseconds >= 1000:
            print(t2,t2.microsecond,t1,t1.microsecond,(t2-t1).seconds)
            break
 
if __name__ == '__main__':
    from timeit import timeit
    t = timeit('timetime()', 'from __main__ import timetime', number=1)
    print(t)
    #print (datetime.datetime.now())

输出

(datetime.datetime(2019, 4, 3, 10, 13, 52, 76548), 76548, datetime.datetime(2019, 4, 3, 10, 13, 52, 75547), 75547, 0) 0.00104904174805

补充:Python datetime去除毫秒 返回当前时间

datetime模块返回当前时间

?
1
2
3
4
import datetime
if __name__ == '__main__':
    a = datetime.datetime.now().replace(microsecond=0)
    print(a, type(a))

运算结果:

2020-05-22 12:13:42 <class 'datetime.datetime'> Process finished with exit code 0

以上为个人经验,希望能给大家一个参考,也希望大家多多支持服务器之家。如有错误或未考虑完全的地方,望不吝赐教。

原文链接:https://blog.csdn.net/weixin_41698305/article/details/88988481