preg_match使用变量？

Question

这是我想要做的。我想要一个简单的方法来添加新的电子邮件，而不必让我的客户端必须触摸主代码。

$list= 'gmail|yahoo|aol'; 


$banned = '\b[\w\.-]+@((?!'.$list.').)[\w\.-]+\.\w{2,4}\b'; 

if (isset($data['email']) && !preg_match($banned, $data['email'])) 
{} 

或许。做一个包括那指向一个文本文件？与域内列出？

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更新

这里是我的代码..

//Banned Domains 
    $banned = 'mailexpire|spamtrail|0815'; 
    // 


    //Emails  
    $email_list = '/^[\w.-]+@((?!'.$banned.').)[\w.-]+\.\w{2,4}$/';    
    if (isset($data['email']) && preg_match($email_list, $data['email'])) 
    { 
     $response->addError('Email Addresses from this domain are not allowed, Please try a different email address', 'email'); 
    } 

    else if (isset($data['email']) && !preg_match($email_list, $data['email'])) 
    { 
     $query = SK_MySQL::placeholder("SELECT COUNT(`profile_id`) FROM `".TBL_PROFILE."` WHERE `email`='?'",$data['email']); 
     if (SK_MySQL::query($query)->fetch_cell()) { 
      $error_msg = SK_Language::text('%forms._fields.email.errors.already_exists'); 
      $response->addError($error_msg,'email'); 
     } 
    } 
    //END 

出于某种原因..其不要再追域？

Answer 1

的问题是，你忘了把模式分隔符：

$banned = '/^[\w.-]+@((?!' . $list . ').)[\w.-]+\.\w{2,4}$/';