From http://www.w3schools.com (Copyright Refsnes Data)
The array_keys() function returns an array containing the keys.
array_keys(array,value) |
Parameter | Description |
---|---|
array | Required. Specifies an array |
value | Optional. You can specify a value, then only the keys with this value are returned |
strict | Optional. Used with the value parameter. Possible values:
|
<?php $a=array("a"=>"Horse","b"=>"Cat","c"=>"Dog"); print_r(array_keys($a)); ?> |
The output of the code above will be:
Array ( [0] => a [1] => b [2] => c ) |
Using the value parameter.
<?php $a=array("a"=>"Horse","b"=>"Cat","c"=>"Dog"); print_r(array_keys($a,"Dog")); ?> |
The output of the code above will be:
Array ( [0] => c) |
Using the strict parameter: false
<?php $a=array(10,20,30,"10"); print_r(array_keys($a,"10",false)); ?> |
The output of the code above will be:
Array ( [0] => 0 [1] => 3 ) |
Using the strict parameter: true
<?php $a=array(10,20,30,"10"); print_r(array_keys($a,"10",true)); ?> |
The output of the code above will be:
Array ( [0] => 3) |
From http://www.w3schools.com (Copyright Refsnes Data)