Return dates of current calendar week as array in PHP5

Question

How would I put together a PHP5 function that would find the current calendar week and return the dates of each day in the week as an array, starting on Monday? For example, if the function were run today (Thu Feb 25 2010), the function would return an array like:

[0] => Mon Feb 22 2010
[1] => Tue Feb 23 2010
[2] => Wed Feb 24 2010
[3] => Thu Feb 25 2010
[4] => Fri Feb 26 2010
[5] => Sat Feb 27 2010
[6] => Sun Feb 28 2010

It doesn't matter what format the dates are stored as in the array, as I assume that'd be very easy to change. Also, it'd be nice to optionally be able to supply a date as a parameter and get the calendar week of that date instead of the current one.

Thanks!

Answer 1

I suppose a solution would be to start by getting the timestamp that correspond to last monday, using strtotime :

$timestampFirstDay = strtotime('last monday');

But if you try with today (thursday), with something like this :

$timestampFirstDay = strtotime('last thursday');
var_dump(date('Y-m-d', $timestampFirstDay));

you'll get :

string '2010-02-18' (length=10)

i.e. last week... For strtotime, "last" means "the one before today".

Which mean you'll have to test if today is "last monday" as returned by strtotime plus one week -- and, if so, add one week...

Here's a possible (there are probably smarter ideas) solution :

$timestampFirstDay = strtotime('last monday');
if (date('Y-m-d', $timestampFirstDay) == date('Y-m-d', time() - 7*24*3600)) {
    // we are that day... => add one week
    $timestampFirstDay += 7 * 24 * 3600;
}

And now that we have the timestamp of "last monday", we can write a simple for loop that loops 7 times, adding 1 day each time, like this :

$currentDay = $timestampFirstDay;
for ($i = 0 ; $i < 7 ; $i++) {
    echo date('Y-m-d', $currentDay) . '<br />';
    $currentDay += 24 * 3600;
}

Which will give us this kind of output :

2010-02-22
2010-02-23
2010-02-24
2010-02-25
2010-02-26
2010-02-27
2010-02-28

Now, up to you to :

• Modify that for loop so it stores the dates in an array
• Decide which format you want to use for the date function

Have fun ;-)

Answer 2

Lessee. . First, to avoid any timezone issues I'd peg to noon on the day you want to compare against, so an hour either way won't cause any problems.

$dateCompare = time(); // replace with a parameter
$dateCompare = mktime(12, 0, 0, date('n', $dateCompare), 
      date('j', $dateCompare), date('Y', $dateCompare));

Then find the day of week of your date.

$dow = date('N', $dateCompare);

1 is Monday, so figure out how many days from Monday we are.

$days = $dow - 1;

Now subtract days worth of seconds until you get back to Monday.

$dateCompare -= (3600 * 24 * $days);

Now assemble your array of days.

$output = array();
for ($x = 0; $x < 7; $x++) {
    $output[$x] = $dateCompare + ($x * 24 * 3600);
}

This is an array of timestamps, but you could store the dates as strings if you prefer.