How to get distinct months from array containing dates - php

Question

I have an array with dates. ie.
array(
0 => '2016-08-01',
1 => '2016-07-15',
2 => '2016-07-01'
);
I need to get the distinct months in array. ie.
array(
0 => 7,
1 => 8
);
I need it to do a foreach to show: June - Juy - August with the distinct months from the dates array. (That part I know how)

Answer 1

You can reformat the date using a combination of array_map, DateTime, and array_unique to achieve that result.
$arr = array(
0 => '2016-08-01',
1 => '2016-07-15',
2 => '2016-07-01'
);
$dates = array_unique(array_map(function($date) {
return DateTime::createFromFormat('Y-m-d', $date)->format('n');
}, $arr));
var_dump($dates);
array(2) {
[0]=>
string(1) "8"
[1]=>
string(1) "7"
}
Of course, it's important to note this results in two dates like 2015-08-11 and 2016-08-04 both showing up as one value in the array. So it's not entirely clear why you would want to do this, but this will meet your specified requirements.

Answer 2

This is the loop you need :
<?php
$arr = array( '2016-08-01',
'2016-07-15',
'2016-07-01' );
$months = array(); // EMPTY ARRAY FOR MONTHS.
foreach ( $arr as $date ) // VISIT EACH DATE IN ARRAY.
{ $mon = substr( $date,5,2 ); // EXTRACT THE MONTH DIGITS.
if ( ! in_array( $mon,$months ) ) // IF MONTH IS NOT IN ARRAY
array_push( $months,$mon ); // INSERT THE MONTH DIGITS.
}
var_dump( $months );
?>
Edit : display month name :
<?php
$arr = array( '2016-08-01',
'2016-07-15',
'2016-07-01' );
$months = array(); // EMPTY ARRAY FOR MONTHS.
foreach ( $arr as $date ) // VISIT EACH DATE IN ARRAY.
{ $mon = substr( $date,5,2 ); // EXTRACT THE MONTH DIGITS.
if ( ! in_array( $mon,$months ) ) // IF MONTH IS NOT IN ARRAY
{ array_push( $months,$mon ); // INSERT THE MONTH DIGITS.
echo date ("F",mktime( null,null,null,$mon,1 ) ); // ◄ MONTH NAME!!!
}
}
?>
Edit #2 : storing month names in array :
<?php
$arr = array( '2016-08-01',
'2016-07-15',
'2016-07-01' );
$months = array(); // EMPTY ARRAY FOR MONTHS.
foreach ( $arr as $date ) // VISIT EACH DATE IN ARRAY.
{ $mon = date("F",mktime( null,null,null,substr( $date,5,2 ),1 ) ); // EXTRACT MONTH.
if ( ! in_array( $mon,$months ) ) // IF MONTH IS NOT IN ARRAY
array_push( $months,$mon ); // INSERT MONTH NAME IN ARRAY.
}
var_dump( $months );
?>

Answer 3

Just use substr on each of your dates array entries to retrieve the chars 5 to 7, then store them in a new array :
$dates = array(
0 => '2016-08-01',
1 => '2016-07-15',
2 => '2016-07-01');
$months = array();
foreach ($dates as $date) {
$months[] = (int)substr($date, 5, 2);
}
$months = array_unique($months); // Remove duplicates
sort($months);