7 comments skip to comment form

1. 

   Drew Douglass said— 12 minutes later

   Nice stuff Brian, I’m assuming array_map() would work similarly to array_filter() in this situation?

   I’m a big fan of these quick one liners, keep them coming buddy!

   #1
2. 

   Paul Scott said— 11 hours later

   As far as I remember, you don’t need the 2nd arg to array_filter to remove NULL values. just $array_without_nulls = array_filter($array_with_nulls); will do

   #2
3. 

   Brian Cray said— 11 hours later

   Paul: Updated. Thanks so much for your valuable and obviously superior knowledge

   #3
4. 

   Cometbus said— 2 days later

   I do not see any way to do this correctly without iterating each item and explicitly unsetting each null. You could pass a unset null function to the array filter, but it is still more than one line. Maybe a regex could get it to one line.

   Currently, this method is dangerous, as it will remove a lot more than just nulls…

   $test_array = array('a', 'b', 'c', '1', '2', '3', null, FALSE, 0, TRUE, 1, '');

   $new_array_without_nulls = array_filter($test_array);

   print_r($test_array);
   print_r($new_array_without_nulls);

   Array
(
[0] => a
[1] => b
[2] => c
[3] => 1
[4] => 2
[5] => 3
[6] =>
[7] =>
[8] => 0
[9] => 1
[10] => 1
[11] =>
)
Array
(
[0] => a
[1] => b
[2] => c
[3] => 1
[4] => 2
[5] => 3
[9] => 1
[10] => 1
)


   As you can see, both false and empty strings were removed. A lot of this has to do with php being a bit strange in what it calls a boolean/null/empty etc.

   Not saying this is not a good thing, just that it could cause you unappreciable behavior. Arrays are often used as a place to store boolean data, and this would clobber that data on the false side of it.

   #4
5. 

   Brian Cray said— 2 days later

   Cometbus:

   You’re right about that. I added my original code for this tutorial, which removes ONLY NULL values.

   #5
6. 

   David said— 3 months later

   is_scalar will work for Cometbus’ sample array.

   #6
7. 

   NXie said— on April 25, 2009 later

   Nice job. Exactly what I was looking for.

   #7
8. 

   Respond to this post—

   Your name

   E-mail address will not be published