检查日期是否是周末 PHP

Here:

function isweekend($year, $month, $day)
{
$time = mktime(0, 0, 0, $month, $day, $year);
$weekday = date('w', $time);
return ($weekday == 0 || $weekday == 6);
}

If you have PHP >= 5.1:

function isWeekend($date) {
return (date('N', strtotime($date)) >= 6);
}

otherwise:

function isWeekend($date) {
$weekDay = date('w', strtotime($date));
return ($weekDay == 0 || $weekDay == 6);
}

The working version of your code (from the errors pointed out by BoltClock):

<?php
$date = '2011-01-01';
$timestamp = strtotime($date);
$weekday= date("l", $timestamp );
$normalized_weekday = strtolower($weekday);
echo $normalized_weekday ;
if (($normalized_weekday == "saturday") || ($normalized_weekday == "sunday")) {
echo "true";
} else {
echo "false";
}


?>

The stray "{" is difficult to see, especially without a decent PHP editor (in my case). So I post the corrected version here.

For guys like me, who aren't minimalistic, there is a PECL extension called "intl". I use it for idn conversion since it works way better than the "idn" extension and some other n1 classes like "IntlDateFormatter".

Well, what I want to say is, the "intl" extension has a class called "IntlCalendar" which can handle many international countries (e.g. in Saudi Arabia, sunday is not a weekend day). The IntlCalendar has a method IntlCalendar::isWeekend for that. Maybe you guys give it a shot, I like that "it works for almost every country" fact on these intl-classes.

EDIT: Not quite sure but since PHP 5.5.0, the intl extension is bundled with PHP (--enable-intl).

Another way is to use the DateTime class, this way you can also specify the timezone. Note: PHP 5.3 or higher.

// For the current date
function isTodayWeekend() {
$currentDate = new DateTime("now", new DateTimeZone("Europe/Amsterdam"));
return $currentDate->format('N') >= 6;
}

If you need to be able to check a certain date string, you can use DateTime::createFromFormat

function isWeekend($date) {
$inputDate = DateTime::createFromFormat("d-m-Y", $date, new DateTimeZone("Europe/Amsterdam"));
return $inputDate->format('N') >= 6;
}

The beauty of this way is that you can specify the timezone without changing the timezone globally in PHP, which might cause side-effects in other scripts (for ex. Wordpress).

If you're using PHP 5.5 or PHP 7 above, you may want to use:

function isTodayWeekend() {
return in_array(date("l"), ["Saturday", "Sunday"]);
}

and it will return "true" if today is weekend and "false" if not.

This works for me and is reusable.

function isThisDayAWeekend($date) {


$timestamp = strtotime($date);


$weekday= date("l", $timestamp );


if ($weekday =="Saturday" OR $weekday =="Sunday") { return true; }
else {return false; }


}

As opposed to testing the explicit day of the week string or number, you can also test using the relative date this weekday of the supplied date.

A direct comparison between the values is not possible without a workaround, as the use of weekday resets the time of the supplied date to 00:00:00.0000.

DateTimeInterface objects

$date->setTime(0, 0, 0) != $date->modify('this weekday');

DateTimeInterface Method

A simple method to implement to ensure the supplied date object is not changed.

function isWeekend(DateTimeInterface $date): bool
{
if ($date instanceof DateTime) {
$date = DateTimeImmutable::createFromMutable($date);
}


return $date->setTime(0,0,0) != $date->modify('this weekday');
}


isWeekend(new DateTimeImmutable('Sunday')); //true

strtotime method

With strtotime you can compare with the date('Yz') format. If the Yz value changes between the supplied date and this weekday, the supplied date is not a weekday.

function isWeekend(string $date): bool
{
return date('Yz', strtotime($dateValue)) != date('Yz', strtotime($dateValue . ' this weekday'));
}


isWeekend('Sunday'); //true

Example

https://3v4l.org/TSAVi

$sunday = new DateTimeImmutable('Sunday');
foreach (new DatePeriod($sunday, new DateInterval('P1D'), 6) as $date) {
echo $date->format('D') . ' is' . (isWeekend($date) ? '' : ' not') . ' a weekend';
}

Result

Sun is a weekend
Mon is not a weekend
Tue is not a weekend
Wed is not a weekend
Thu is not a weekend
Fri is not a weekend
Sat is a weekend