用PHP查找下一个数组行

Question

I'm working in a code that find the next array value based on the current value but still always returning 1 as result.

$users_emails = array('Spence', 'Matt', 'Marc', 'Adam', 'Paul');

$current = 'Spence';
$keys = array_keys($users_emails);
$ordinal = (array_search($current,$keys)+1);
$next = $keys[$ordinal];
echo $next;

What's wrong?

Answer 1

You are searching the wrong array to start with and echoing the wrong array too.

$users_emails = array('Spence', 'Matt', 'Marc', 'Adam', 'Paul');

$current = 'Spence';
$ordinal = (array_search($current,$users_emails)+1);
$next = $users_emails[$ordinal];
echo $next;

See my code, I search for Spence in the array with names and it returns a key number.
This key number should echo in user emails not keys.

https://3v4l.org/0gJ1m

---

If you need it to work with associative arrays you need to do like this:

 $users_emails = array('a' => 'Spence', 'b' => 'Matt', 'c' => 'Marc', 'd' => 'Adam', 'e' => 'Paul'); $keys = array_values(array_keys($users_emails)); $current = 'Matt'; $next = ""; // set to not get notice if end of array $ordinal = array_search($current,$users_emails); $nextkey = (array_search($ordinal, $keys)+1); If(!isset($keys[$nextkey])){ // what to do if your at the end of array // $nextkey = 0; // Echo "message"; // Or whatever you want }else{ $next = $users_emails[$keys[$nextkey]]; } echo $next; 

I use array_values on the keys to get a indexed array that accepts +1 to find the next key in the array.

https://3v4l.org/iVO6U

Answer 2

$keys are the keys , not the value . Use the array with the $ordinal .

$next = $users_emails[$ordinal];

Demo: https://3v4l.org/REhGr

The array_keys gives you an array of the key s. Use your normal array for the array_search as well. Here's a visual of what you currently are building for $keys .

Array
(
    [0] => 0
    [1] => 1
    [2] => 2
    [3] => 3
    [4] => 4
)

Demo: https://3v4l.org/GQQcF

$users_emails = array('Spence', 'Matt', 'Marc', 'Adam', 'Paul');
$current = 'Marc';
$ordinal = (array_search($current, $users_emails)+1);
$next = !empty($users_emails[$ordinal]) ? $users_emails[$ordinal] : FALSE;
echo $next;

Answer 3

Just use this one:

$users_emails = array('Spence', 'Matt', 'Marc', 'Adam', 'Paul');

$current = 'Spence';
$ordinal = array_search($current,$users_emails) + 1;
$next = $users_emails[$ordinal];
echo $next;

Answer 4

Here's what I mean:

<?php
$users_emails = array('Spence', 'Matt', 'Marc', 'Adam', 'Paul');
$current = 'Spence'; $ordinal = array_search($current, $user_emails)+1;
$next = $user_emails[$ordinal];
echo $next;
?>

Depending what you're doing you may want to use next() instead:

<?php
$user_emails = array('Spence', 'Matt', 'Marc', 'Adam', 'Paul');
$current = current($user_emails); $next = next($user_emails); reset($user_emails);
echo $next;
?>

Answer 5

I have checked your code. In your code, array_keys function returns the indexes of $users_email as:

Array ( [0] => 0 [1] => 1 [2] => 2 [3] => 3 [4] => 4 )

Now you are searching $current = 'Spence'; in indexes array. That's why it returns 1 .

You want the next value of searched string you should as:

$users_emails = array('Spence', 'Matt', 'Marc', 'Adam', 'Paul');

    $current = 'Spence';
    //$keys = array_keys($users_emails);//print_r($keys);
    $ordinal = (array_search($current,$users_emails)+1);
    $next = $users_emails[$ordinal];
    echo $next;

output:

Matt