针对关联（一维）数组的特定部分？

Question

I want to try to swap the first and last index's of this array:

 <?php
 $their_name = array(
      'Jim'   => 'dad', 
      'Josh'  => 'son', 
      'Jamie' => 'mom', 
      'Jane'  => 'daughter', 
      'Jill'  => 'daughter'
 );
 ?>

So that it will look like this:

 <?php
 $their_name = array(
      'Jill'   => 'dad', 
      'Josh'  => 'son', 
      'Jamie' => 'mom', 
      'Jane'  => 'daughter', 
      'Jim'  => 'daughter'
 );
 ?>

I did something similar last night with an array using these:

$temp                   = $user_name[0];     
$user_name[0]           = end($user_name);    
$count                  = count($user_name);  
$user_name[$count-1]    = $temp;             
return $user_name;                            

I'm assuming that these methodology will be similar. However, $their_name[0] returns 'J'.

Thanks!

Answer 1

Here's a potential solution to your specific problem...

$their_name = array(
  'Jim'   => 'dad', 
  'Josh'  => 'son', 
  'Jamie' => 'mom', 
  'Jane'  => 'daughter', 
  'Jill'  => 'daughter'
);
// rewind array pointer to first element
reset($their_name);
// get key name
$firstKey = key($their_name);
// get value and remove from array
$firstValue = array_shift($their_name);

// advance pointer to last element 
end($their_name);
// get key name
$lastKey = key($their_name);
// get value and remove from array
$lastValue = array_pop($their_name);

// first element using last key and first value
$firstElement = array($lastKey => $firstValue);
// last element using first key and last value
$lastElement = array($firstKey => $lastValue);

// add them to the remaining elements 
$their_name = $firstElement + $their_name + $lastElement;

var_dump($their_name);
// Result:
array(5) {
    ["Jill"]=>
    string(3) "dad"
    ["Josh"]=>
    string(3) "son"
    ["Jamie"]=>
    string(3) "mom"
    ["Jane"]=>
    string(8) "daughter"
    ["Jim"]=>
    string(8) "daughter"
}