When I search and read code about time & date problems developers have, I noticed that a lot of people still use the old PHP functions like date(), time() or strtotime().
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What about using the class DateTime instead?
DateTime can vì all the usual date and time operations you could ask for, và even more. Using DateTime can save a lot of time when you have to vì simple, or more complex operations on dates.
Now I see you asking: why using DateTime instead of a bunch of PHP date functions?
Here’s why:DateTime is definitely more robust khổng lồ use. Less bug is always better.DateTime is a class. You can use composition to lớn modify his behavior easily. You need always the same date as input for your unit tests? Use your own instance of DateTime which always return the birthday of your dog!Using one class is easier to lớn understand for your fellow developer colleagues. Even if they don’t know DateTime, they just have to look to lớn the documentation for one single class. It is definitely better than looking for a bunch of independent functions.
DateTime Instantiation và Formatting
The instantiation is easy: you can pass khổng lồ the constructor a date correctly formatted, or nothing if you want to use the actual date and time.
Here the các mục of supported date & time formats you can inject in the constructor.
You can then format the date in order lớn display it, in two lines of code:
$dateTime = new DateTime();echo $dateTime->format('Y-m-d H:i:s');`
Output: whatever the current date is, correctly formatted.
Easy, isn’t it? You can as well precise the timezone you want as a second argument:
DateTime và TimestampsYou want khổng lồ format an unreadable timestamp into a nice và shiny easy-to-read date?
$dateTime = new DateTime();$dateTime->setTimestamp(1271802325);echo $dateTime->format('Y-m-d H:i:s');
Obviously you can as well output a timestamp if you need to:
Adding or Subtracting Time
What about adding or retrieving a day, a minute, an hour of a date? You only need to use the proper formatting:
You can as well use the constructor if you work on the current date:
$dateTime = new DateTime('+1d');echo $dateTime->format('Y-m-d H:i:s');`
Output the current date plus one day.
For the same result, you could as well instantiate the class DateInterval but you would have to use an interval specification which is way harder to read.
I never use this last solution personally, simply because I never need to.
Interval Between Different Dates
It’s very easy lớn use DateTime classes lớn compare dates:
Output: 00-0-1 22:0:0
In this example we created two DateTime objects. They will receive two different dates in their constructors.
In order lớn compare those two dates we use the method diff() of the first DateTime object with the second DateTime object as argument.
The diff() method will return a new object of type DateInterval. If you want to lớn format the difference between the two dates, you can use as well the format() method of the class DateInterval but be careful: it won’t accept the same formatting as the DateTime::format() method.
The output indicate that there is 1 day and 22 hours difference between the two dates.
If you only want the seconds, hours or day of interval you can write:
Comparing DateTimesIf you need lớn compare two instances of DateTime, it’s as simple as writing:
Output: datetime1 lesser than datetime2
Keep in mind that you need PHP 5.2.2 or greater for the comparisons lớn work. I really hope it’s the case!
You’re Now a Master of DateTime!
I invite you to lớn read the PHP documentation about the class DateTime. You will never have to lớn mess around with multiple functions & you will simplify your code a big time. Your colleague will praise you and your skills till the kết thúc of time.
Glory & fame will be at your door!
If you know other tricks và techniques with DateTime, feel không tính phí to nội dung your knowledge in the phản hồi section.
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