PHP array_keys() Function
Example
Return an array containing the keys:
<?php
$a=array("Volvo"=>"XC90","BMW"=>"X5","Toyota"=>"Highlander");
print_r(array_keys($a));
?>
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Definition and Usage
The array_keys() function returns an array containing the keys.
Syntax
array_keys(array, value, strict)
Parameter Values
| 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:
|
Technical Details
| Return Value: | Returns an array containing the keys |
|---|---|
| PHP Version: | 4+ |
| Changelog: | The strict parameter was added in PHP 5.0 |
More Examples
Example
Using the value parameter:
<?php
$a=array("Volvo"=>"XC90","BMW"=>"X5","Toyota"=>"Highlander");
print_r(array_keys($a,"Highlander"));
?>
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Example
Using the strict parameter, false:
<?php
$a=array(10,20,30,"10");
print_r(array_keys($a,"10",false));
?>
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Example
Using the strict parameter, true:
<?php
$a=array(10,20,30,"10");
print_r(array_keys($a,"10",true));
?>
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❮ PHP Array Reference
