PHP - Remove duplicate values in an array based on a key's value and empty values

Question

I have the following output from a PHP array:

Array ( 
[0] => Array ( 
     [set1] => Array ( 
            [link] => xyz.com/def
            [time] => 2016-01-03
    [set2] => Array ( 
            [link] => 
            [time] => ) 
    [set3] => Array ( 
            [link] => 
            [time] => ) 
    ) 
[1] => Array ( 
    [set1] => Array ( 
            [link] => xyz.com/123
            [time] => 2016-01-03) 
    [set2] => Array ( 
            [link] => 
            [time] => ) 
    [set3] => Array ( 
            [link] => xyz.com/123
            [time] => 2016-01-03) 
    ) 
[2] => Array ( 
    [set1] => Array ( 
            [link] => xyz.com/abc
            [time] => 2015-12-03) 
    [set2] => Array (
            [link] => xyz.com/abc
            [time] => 2016-01-03) 
    [set3] => Array ( 
            [link] => xyz.com/123456
            [time] => 2016-01-03) 
    ) )

I would like to eliminate duplicate [link] regardless of the [time] - then I would like to eliminate the empty [link] values such as [0][set2], and finally have an output as follows:

[link] => xyz.com/def
[time] => 2016-01-03

[link] => xyz.com/123
[time] => 2016-01-03) 

[link] => xyz.com/abc
[time] => 2015-12-03

[link] => xyz.com/123456
[time] => 2016-01-03

This is what I tried:

$categoryUrlArray= array_unique(($categoryUrlArray, SORT_REGULAR);
    foreach ($categoryUrlArray as $categoryUrlLevel01) {
        $categoryUrlLevel01= array_unique($categoryUrlLevel01, SORT_REGULAR);
        foreach ($categoryUrlLevel01 as $categoryUrlLevel02) {
            echo $categoryUrlLevel02['link'];
            echo '<br/>';
            echo $categoryUrlLevel02['time'];
            echo '<br/><br/><br/>';
        }
    }

The problem with the above code is that duplicates are not being eliminated and empty values are still showing i.e. there are plenty of line breaks <br/> - that is why I know they are not being eliminated.

No it doesn't I use <br/> to make it more user friendly when the result is output. — xltmt
– xltmt, Commented Jan 4, 2016 at 7:28

roullie · Accepted Answer · 2016-01-04 07:37:15Z

how about just checking inside the inner loop for blanks and duplicates? then save them all inside a new variable. like this

$newArr = array();
$links = array();
foreach($categoryUrlArray as $urls){
    foreach($urls as $url){
        if(!empty($url['link']) && !in_array($url['link'],$links)){
            $newArr[] = $url;
            $links[] = $url['link'];
        }
    }
}
var_dump($newArr);

will result to

array(4) {
  [0]=>
  array(2) {
    ["link"]=>
    string(11) "xyz.com/def"
    ["time"]=>
    string(10) "2016-01-03"
  }
  [1]=>
  array(2) {
    ["link"]=>
    string(11) "xyz.com/123"
    ["time"]=>
    string(10) "2016-01-03"
  }
  [2]=>
  array(2) {
    ["link"]=>
    string(11) "xyz.com/abc"
    ["time"]=>
    string(10) "2015-12-03"
  }
  [3]=>
  array(2) {
    ["link"]=>
    string(14) "xyz.com/123456"
    ["time"]=>
    string(10) "2016-01-03"
  }
}

Samir Selia · Accepted Answer · 2016-01-04 07:39:00Z

0

Just add a condition to check if link is not blank !empty($categoryUrlLevel02['link'])

Below is the modified code:

($categoryUrlArray= array_unique(($categoryUrlArray, SORT_REGULAR);
foreach ($categoryUrlArray as $categoryUrlLevel01) {
    $categoryUrlLevel01= array_unique($categoryUrlLevel01, SORT_REGULAR);
    foreach ($categoryUrlLevel01 as $categoryUrlLevel02) {
        if(!empty($categoryUrlLevel02['link']))
        {
            echo $categoryUrlLevel02['link'];
            echo '<br/>';
            echo $categoryUrlLevel02['time'];
            echo '<br/><br/><br/>';
        }
    }
}

answered Jan 4, 2016 at 7:39

Samir Selia

7,1502 gold badges14 silver badges33 bronze badges

Comments

mickmackusa · Accepted Answer · 2018-09-25 13:23:08Z

Best practice for efficiently identifying unique values in your result array is accomplished by assigning temporary keys in the result array and checking !isset() for the identifying key (which is the link value). If you don't want to see these redundant/temporary keys in your output, call array_values().

*note, making iterated calls of in_array() is certainly more costly in terms of performance versus isset().

Code: (Demo)

$categoryUrlArray = [
    [
        "set1" => ["link" => "xyz.com/def", "time" => "2016-01-03"],
        "set2" => ["link" => "", "time" => ""],
        "set3" => ["link" => "", "time" => ""]
    ],
    [
        "set1" => ["link" => "xyz.com/123", "time" => "2016-01-03"],
        "set2" => ["link" => "", "time" => ""],
        "set3" => ["link" => "xyz.com/123", "time" => "2016-01-03"]
    ],
    [
        "set1" => ["link" => "xyz.com/abc", "time" => "2016-12-03"],
        "set2" => ["link" => "xyz.com/abc", "time" => "2016-01-03"],
        "set3" => ["link" => "xyz.com/123456", "time" => "2016-01-03"]
    ]
];

foreach ($categoryUrlArray as $groups) {
    foreach ($groups as $row) {
        if ($row["link"] && !isset($result[$row["link"]])) {  if "truthy" (not empty) and unique
            $result[$row["link"]] = $row;
        }
    }
}
var_export(array_values($result));

Output:

array (
  0 => 
  array (
    'link' => 'xyz.com/def',
    'time' => '2016-01-03',
  ),
  1 => 
  array (
    'link' => 'xyz.com/123',
    'time' => '2016-01-03',
  ),
  2 => 
  array (
    'link' => 'xyz.com/abc',
    'time' => '2016-12-03',
  ),
  3 => 
  array (
    'link' => 'xyz.com/123456',
    'time' => '2016-01-03',
  ),
)

Collectives™ on Stack Overflow

PHP - Remove duplicate values in an array based on a key's value and empty values

3 Answers 3

Comments

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related