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EtdashouFlag for Canada

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Get number of weeks for a given month with PHP

Hello all,

Question is simple, however I have difficulty to create a function that would return this value.

September 2012, their is 5 weeks in this month.
February 2011, their is 4 weeks in this month.

How can I find this with a PHP function? Is it possible?

Thank you
Avatar of Lukasz Chmielewski
Lukasz Chmielewski
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Avatar of Ultra_Master
Ultra_Master

The correct code is the following:
<?php

function weeks($month, $year){
        $num_of_days = date("t", mktime(0,0,0,$month,1,$year)); 
        $lastday = date("t", mktime(0, 0, 0, $month, 1, $year)); 
        $no_of_weeks = 0; 
        $count_weeks = 0; 
        while($no_of_weeks < $lastday){ 
            $no_of_weeks += 7; 
            $count_weeks++; 
        } 
	return $count_weeks;
} 

echo weeks(2,2011)."<br/>";
echo weeks(9,2012)."<br/>";

?>

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Avatar of Etdashou

ASKER

hmmm.. Let me test that. I think I haven't ask my question correctly and it is my fault.

If you take a calendar, you see some months have 5 lines of "week". Some have 6, some have 4. This is the number I'm looking for.

But let me test your code.
So it depends on the day of week that is a month "starter".
In that case use the following code:
And, btw, your reasoning was wrong about feb 2011. According to your previous statement you said it has 4 weeks, while it has days distributed over 5 weeks as you can see from the attached picture.
<?php

function weeks($month, $year){
        $firstday = date("w", mktime(0, 0, 0, $month, 1, $year)); 
        $lastday = date("t", mktime(0, 0, 0, $month, 1, $year));
        $count_weeks = 1 + ceil(($lastday-8+$firstday)/7);
        return $count_weeks;
} 
echo weeks(2,2011)."<br/>";
echo weeks(9,2012)."<br/>";

?>

Open in new window

User generated image
Ultra Master, you are right, I was wrong with the four weeks.

I tried your code and it seems to work. However, if you look at July 2011, their is 6, however your code output 5. Is it possible because it is Sunday the last day of the month?
hmmm
Where I live, the first day of the week is Sunday, not Monday. Is this a problem with your code?
July 2011 is 5 not 6. See the attached picture to convince yourself.
But July 2012 is 6. Apparently the counting begins from Sunday and I considered it starting from Monday so use the following updated code and it should work on whatever example.
<?php
function weeks($month, $year){
        $firstday = date("w", mktime(0, 0, 0, $month, 1, $year)); 
        $lastday = date("t", mktime(0, 0, 0, $month, 1, $year)); 
	if ($firstday!=0) $count_weeks = 1 + ceil(($lastday-8+$firstday)/7);
	else $count_weeks = 1 + ceil(($lastday-1)/7);
  return $count_weeks;
} 
echo weeks(2,2011)."<br/>";
echo weeks(7,2011)."<br/>";
echo weeks(7,2012)."<br/>";

?>

Open in new window

July2011.png
I attached a picture of my calendar. It is from Quebec - Canada (French).
Weeks start on Sunday (= Di = Dimanche).
Using your new functions I have different results.

echo weeks(2,2011)."<br/>"; 5
echo weeks(7,2011)."<br/>"; 5
echo weeks(7,2012)."<br/>"; 6


I am sorry for this...
cal-sunday.png
cal-sunday-2012.png
I'm just curious but I wouldn't be myself without asking this. What is the purpose of this kind of week calculation ? Will it be used only with your local timezone ?
I actually create a Calendar in PHP. It is in a Table and I would like to adjust the rowspan for a <td> with the number of weeks that this month will have. It would help me also to use a button that goes from week to week when you press "next" or "previous". If I am on week 5/6, I won't change month, etc.

I didn't realize it would be that much difficult and that I should consider so much conditions, like starting day of a week=Sunday.

I could perhaps add more points to this question.
Oh and yes it will be used only in my timezone.
Could you post your calendar code here ? It would be easier to work with that.
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Ultra_Master

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Ultra Master, you rock!

Thank you.