create_function in php [duplicate]

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Closed 9 years ago.

Possible Duplicate:
Is there a PHP function to remove any/all key/value pairs that have a certain value from an array?
Remove zero values from a PHP array

I have one array like this.

[notify_emp] => Array
  (
      [224] => 0
      [228] => 0
      [232] => 1
      [250] => 1
      [350] => 1
  )

I want only those keys from the array which have value set to 1 and need to remove keys that have value 0. how can I do this using create_function in php ? or is there any other way to perform the action?

Answer 1

Try this:

<?php
function hasOne($var)
{
    // returns whether the input has 1
    return($var == 1);
}


$arr= array("224"=>1, "228"=>0, "250" => 1);

print_r(array_filter($arr, "hasOne"));
?>

Which results in:

Array ( [224] => 1 [250] => 1 ) 

Answer 2

$array = array_filter($array, create_function('$val', 'return (bool) $val;'));

...or for PHP >= 5.3:

$array = array_filter($array, function ($val) {
  return (bool) $val;
});

...or simply (as @outis rightly points out) you can simply

$array = array_filter($array);

...or you could just:

foreach ($array as $k => $v) {
  if (!$v) unset($array[$k]);
}

Take your pick.

However, I guess what you want is a list of items with an "on" flag, so this might be a better approach:

$flaggedAsOn = array_keys($array,'1');

Answer 3

If you're using PHP 5.3 then using array_filter with an anonymous function is a lot less mucking around.

If you're using a version of PHP prior to 5.3 then just implementing a function for use as a callback with array_filter is less mucking around than using create_function().

Answer 4

remove_unwanted ($array) {

   foreach ($array as $key => $value) {

      if ($array[$key] == '0') { unset($array[$key]) }

   }

}