Removing null values from an array in PHP

Question

I want to remove empty values from an array. I have tried array_filter, array_diff and a custom coded function but nothing helped.

Here's my code that generates the array:

for($i=0;$i<$_POST['size'];$i++)
{
    $e = array();
    if(!@strcasecmp("yes", $_POST['email'.$i]))
    {
        //array_push($e, $_POST['u'.$i]);
        $e[$i] = $_POST['u'.$i];
    }
    else
    {
        $e[$i] = "";
    }
    //var_dump($e);

var_dump($e);
}

My var_dump outputs:

array (size=1)
  0 => string '12' (length=2)
string '12' (length=2)
array (size=1)
  1 => string '13' (length=2)
string '13' (length=2)
array (size=1)
  2 => string '' (length=0)
string '' (length=0)
array (size=1)
  3 => string '' (length=0)
string '' (length=0)
array (size=1)
  4 => string '' (length=0)
string '' (length=0)
array (size=1)
  5 => string '' (length=0)

How would I remove these empty indexes? Any suggestions are welcome.

@Dragon I don't think so. I only need the value 12,13 in the array..so I could later use implode and then convert it to a string. — user3369276
– user3369276, Commented Jul 20, 2014 at 21:23
Are you initialising that array in the right place? You are resetting the ith value in each iteration, but it is being wiped at every iteration too. Looks like that initialisation should go before the loop? — halfer
– halfer, Commented Jul 20, 2014 at 21:29
I'm guessing the else clause is the problem - that seems to be what is adding the last four empty-string entries. Remove it and see if that helps? — halfer
– halfer, Commented Jul 20, 2014 at 21:30
OP, use tab completion to get your reply-handles correct. The above is @Dagon, not Dragon. — halfer
– halfer, Commented Jul 20, 2014 at 22:37

Fabricator · Accepted Answer · 2014-07-20 21:42:12Z

1

The elements you want to remove are not null, they are empty strings. You can still use array_filter like the following

$filtered_array = array_filter($e, 'strlen');

We use strlen as the callback function because empty string return 0 and is evaluated to false in PHP. Actually the following also works as pointed out by @revo:

$filtered_array = array_filter($e);

edited Jul 20, 2014 at 21:42

answered Jul 20, 2014 at 21:32

Fabricator

12.8k2 gold badges29 silver badges40 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Fabricator Over a year ago

@revo, thanks for pointing it out. I just assumed it didn't work because OP said it didn't...

MatsLindh · Accepted Answer · 2014-07-20 21:33:19Z

You can use name="email[]" to get an indexed array from your POST, so you can drop 'size' and just foreach over the array instead. Move the initalization of $e out, as you're resetting it for each iteration.

if (isset($_POST['email']) && is_array($_POST['email'])) {
    $e = array();

    foreach ($_POST['email'] as $email) {
        if (trim($email)) {
            $e[] = $email;
        }
    }

    var_dump($e);
}

.. if you really want to keep the worse method with 'size' and for, remove the is_array check and replace with your own loop structure, but keep the internal checks and move $e initialization out from your for loop.

Steve · Accepted Answer · 2014-07-20 21:37:53Z

0

What is the point of the else condition? Simply omit it:

for($i=0;$i<$_POST['size'];$i++)
{
    $e = array();
    if(!@strcasecmp("yes", $_POST['email'.$i]))
    {
        //array_push($e, $_POST['u'.$i]);
        $e[] = $_POST['u'.$i];
    }

var_dump($e);
}

answered Jul 20, 2014 at 21:37

Steve

20.5k5 gold badges47 silver badges70 bronze badges

Collectives™ on Stack Overflow

Removing null values from an array in PHP

3 Answers 3

1 Comment

Comments

Comments

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

Comments

Comments

Related