PHP array function sequence array_search()-return key name by element value_PHP tutorial

array_search() definition and usage
array_search() function is the same as in_array(), searching for a key value in the array. If the value is found, the key of the matching element is returned. If not found, returns false.

Prior to PHP 4.2.0, functions returned null instead of false on failure.

If the third parameter strict is specified as true, the key name of the corresponding element will only be returned if the data type and value are consistent.

Syntax
array_search(value,array,strict) Parameter Description
value Required. Specifies the value to search for in the array.
array required. The array to be searched.
strict optional. Possible values:

true
false - Default
If the value is set to true, the type of the given value will also be checked in the array. (See Example 2)


Example 1