帶有常量的PHP類變量

Question

我得到常量（DEPLOYMENT）行上的解析錯誤。爲什麼現在被允許，或者我錯過了什麼。

解析錯誤：解析錯誤，期待` '）'」在

class UploadComponent extends Object { 

    private $config = array(
     'accessKey' => 'XXXX', 
     'secretKey' => 'XXXX', 

     'images' => array(
      'bucket' => DEPLOYMENT.'-files/images', 
      'dns' => false 
     ), 

     'files' => array(
      'bucket' => DEPLOYMENT.'-files/files', 
      'dns' => false 
     ), 

     'assets' => array(
      'bucket' => DEPLOYMENT.'-files/assets', 
      'dns' => false 
     ) 
    ); 
    .... 
} 

Answer 1

當定義類瓦爾不能使用變量。初始化數組構造函數，而不是內部：

class UploadComponent extends Object { 

    private $config; 

    function __construct() { 
     $this->config = array(
      'accessKey' => 'XXXX', 
      'secretKey' => 'XXXX', 

      'images' => array(
       'bucket' => DEPLOYMENT.'-files/images', 
       'dns' => false 
      ), 

      'files' => array(
       'bucket' => DEPLOYMENT.'-files/files', 
       'dns' => false 
      ), 

      'assets' => array(
       'bucket' => DEPLOYMENT.'-files/assets', 
       'dns' => false 
      ) 
     ); 
    } 
} 

Answer 2

的原因是「常量」可以動態定義。因此，它們的內容僅在運行時才知道，而不是編譯時。