What's the best way to compare the current datetime to a time of day that includes minutes. My current method doesn't seem the most concise. I want to execute a statement after 6:30PM.

from datetime import datetime as dt

if (dt.now().hour == 18 and dt.now().minute > 30) or dt.now().hour >= 19:
    print('hello world')

It gets even messier if I want to do after 6:30PM and before 9:30PM.

CodePudding user response：

I would do this:

from datetime import datetime

def check_time(date, hour, minute):
    if date > date.replace(hour=hour, minute=minute):
        print('its more than '   str(hour)   ':'   str(minute))
    else:
        print('its less than '   str(hour)   ':'   str(minute))

today = datetime.now()
check_time(today, 18, 30)

CodePudding user response：

You can use this function which I built for one of my projects. I had this function built at day, hour, minute, second level. I have reduced it for your needs.

def compare_hours(constraint: dict) -> bool:
    from datetime import datetime
    """
    This is used to compare a given hours,minutes against current time
    The constraint must contain a single key and value.
    Accepted keys are: 
        1. before:
            eg {"before": "17:30"}
        2. after:
            eg: {"after": "17:30"}
        3. between:
            eg: {"between": "17:30, 18:30"}
        4. equal:
            eg: {"equal": "15:30"}

    Parameters
    ----------
    constraint : dict
        A dictionary with keys like before, after, between and equal with their corresponding values.

    Returns
    -------
    True if constraint matches else False

    """
    accepted_keys = ("before", "after", "between", "equal")
    assert isinstance(constraint, dict), "Constraint must be a dict object"
    assert len(constraint.keys()) == 1, "Constraint contains 0 or more than 1 keys, only 1 is allowed"
    assert list(constraint.keys())[0] in accepted_keys, f"Invalid key provided. Accepted keys are {accepted_keys}"
    key = list(constraint.keys())[0]
    time_split = lambda x: list(map(int, x.split(":")))
    try:
        if key == "before":
            hours, minutes = time_split(constraint.get(key))
            dt = datetime.now()
            if dt < dt.replace(hour=hours, minute=minutes):
                return True
            return False
        elif key == "after":
            hours, minutes = time_split(constraint.get(key))
            dt = datetime.now()
            if dt > dt.replace(hour=hours, minute=minutes):
                return True
            return False
        elif key == "between":
            dt = datetime.now()
            values = constraint.get(key).replace(' ', '').split(",")
            assert len(values) == 2, "Invalid set of constraints given for between comparison"
            hours, minutes = time_split(values[0])
            dt1 = dt.replace(hour=hours, minute=minutes)
            hours, minutes = time_split(values[1])
            dt2 = dt.replace(hour=hours, minute=minutes)
            assert dt2 > dt1, "The 1st item in between must be smaller than second item"
            if dt > dt1 and dt < dt2:
                return True
            return False
        else:
            hours, minutes = time_split(constraint.get(key))
            dt = datetime.now()
            if dt == dt.replace(hour=hours, minute=minutes):
                return True
            return False
    except Exception as e:
        print(e)

You can reuse the function for your need. For eg:

if compare_hours({"before": "21:00"}) and compre_hours({"after": "18:30"}):
    "do something"

This is essentially the same as using the "between" option.

CodePudding user response：

You can simply extract a time object from your datetime object and make a direct comparison.

>>> from datetime import time, datetime as dt
>>> dt.now()
datetime.datetime(2022, 3, 8, 15, 0, 56, 393436)
>>> dt.now().time() > time(14, 30)
True
>>> dt.now().time() > time(15, 30)
False