如何动态定义关联数组键？

Question

我有两个变量：

$keystr = 'plant,fruit,exotic'; 
$value='kiwi'; 

如何创建关联数组？

$arr = ('plant'=>array('fruit'=>array('exotic'=>'kivi'))); 

Answer 1

$keystr = 'plant,fruit,exotic'; 
$value='kiwi'; 

$arr = array(); 
$current = &$arr; 
$keys = explode(',', $keystr); 
foreach($keys as $key) { 
    $current[$key] = array(); 
    $current = &$current[$key]; 
} 
$current = $value; 
unset($current); 
var_dump($arr); 

的示范见http://ideone.com/YiMIRb