我的PHP代碼與遞歸方法有什麼問題？

Question

這裏是我的PHP代碼，測試方法不給想要的輸出，另一個奇怪的事情是var_dump（'a'）打印3次;

我想要的輸出是數組（'qtggccc'，'qtff23sdf'）;

public function main() 
{ 
    $serverIds = array('ff23sdf','ggccc'); 
    $res = $this->test($serverIds); 
    var_dump($res); 
} 

public function test($serverIds,$imgArray = array()) 
{ 
    if(count($serverIds) > 0){ 
     $media_id = array_pop($serverIds); 
     $imgUrl= $this->hh($media_id); 
     array_push($imgArray,$imgUrl); 
     var_dump($serverIds); 
     var_dump($imgArray); 
     $this->test($serverIds,$imgArray); 
    } 
    var_dump('a'); 
    return $imgArray; 
} 

public function hh($m) 
{ 
    return 'qt'.$m; 
} 

Answer 1

試試這個：

class MyClass{ 

    private $imgArray = array(); 

    public function main(){ 

    $serverIds = array('ff23sdf','ggccc'); 
    $res = $this->test($serverIds); 
    print_r($this->imgArray); 
    } 

    public function test($serverIds){ 

    if(count($serverIds) > 0){ 
     $media_id = end($serverIds); 
     $imgUrl= $this->hh($media_id); 
     array_push($this->imgArray,$imgUrl); 
     //remove last element 
     array_pop($serverIds); 
     $this->test($serverIds); 
    } 
    return; 
} 

    public function hh($m){ 
    return 'qt'.$m; 
    } 
} 

$obj = new MyClass(); 
echo '<pre>'; 
$obj->main(); 

Answer 2

爲什麼使用遞歸？您正在爲一個簡單的問題使用複雜的解決方案。

public function main() 
{ 
    $serverIds = array('ff23sdf','ggccc'); 
    $res = array(); 

    //These three lines replace an entire recursive function, making the code easier and saving a chunk of memory once you start using real arrays 
    foreach ($serverIds as $media_id){ 
     array_unshift($res, $this->hh($media_id)); 
    } 
    var_dump($res); 
} 

public function hh($m) 
{ 
    return 'qt'.$m; 
}