$iterator->keyOf()
Tries to find the key for the given element
$iterator->keyOf(mixed $needle): string|falseParameters
| Name | Type | Default | Description | 
|---|---|---|---|
| $needle * | mixed | – | the element to search for | 
Return type
string|false
Tries to find the key for the given element
$iterator->keyOf(mixed $needle): string|false| Name | Type | Default | Description | 
|---|---|---|---|
| $needle * | mixed | – | the element to search for | 
string|false