如果我只有值，我如何获得数组元素的键？

Question

How do i get the key of an array element if i only have the value?

So i have this array and i need the key of an email address with the value

$users_emails = array(
 'Spence' => '[e-mail]', 
  'Matt'   => '[e-mail]', 
  'Marc'   => '[e-mail]', 
  'Adam'   => '[e-mail]', 
  'Paul'   => '[e-mail]');

How do i get the 'Adam' if all i have is the value '[e-mail]'.. so basically how do i get the key if i have the value

Answer 1

Use array_search and this question.

Example from docs:

<?php
$array = array(0 => 'blue', 1 => 'red', 2 => 'green', 3 => 'red');

$key = array_search('green', $array); // $key = 2;
$key = array_search('red', $array);   // $key = 1;
?>

PHP has wonderful documentation and it's quite easy to find the basic stuff with Google.

<?php
$key = array_search('[e-mail]', $users_emails); // $key = 'Spence';
?>