小编Dio*_*jen的帖子

我有一个常量，我想通过这样的函数返回：

public function getConst($const)
{
    $const = constant("Client::{$const}");
    return $const;
}

但这给了我一个错误：

constant(): Couldn't find constant Client::QUERY_SELECT

然而，这确实有效：

public function getConst($const)
{
    return Client::QUERY_SELECT;
}

为什么不？

我正在学习Symfony2,非常酷的东西.但是当我想尝试访问生产环境时,我确实遇到了一些麻烦.我已经按照位于此处的Symblog教程进行了操作:http://tutorial.symblog.co.uk/

我已经清除了缓存,我访问了http://symfony.dev/我在本地运行.页面保持完全空白,此错误在日志中:

Fatal error: Uncaught exception 'Doctrine\ORM\ORMException' with message 'Unknown Entity namespace alias 'DSBlogBundle'.' 
in /Applications/MAMP/htdocs/symfony/vendor/doctrine/orm/lib/Doctrine/ORM/ORMException.php:236 
Stack trace: 
#0 /Applications/MAMP/htdocs/symfony/vendor/doctrine/orm/lib/Doctrine/ORM/Configuration.php(194): Doctrine\ORM\ORMException::unknownEntityNamespace('DSBlogBundle') 
#1 /Applications/MAMP/htdocs/symfony/vendor/doctrine/orm/lib/Doctrine/ORM/Mapping/ClassMetadataFactory.php(554): Doctrine\ORM\Configuration->getEntityNamespace('DSBlogBundle') 
#2 /Applications/MAMP/htdocs/symfony/vendor/doctrine/common/lib/Doctrine/Common/Persistence/Mapping/AbstractClassMetadataFactory.php(194): Doctrine\ORM\Mapping\ClassMetadataFactory->getFqcnFromAlias('DSBlogBundle', 'Blog') 
#3 /Applications/MAMP/htdocs/symfony/vendor/doctrine/orm/lib/Doctrine/ORM/EntityManager.php(295): Doctrine\Common\Persistence\Mapping\AbstractClassMetadataFactory->getMetadataFor('DSBlogBundle:Bl...') 
#4 /Applications/MAMP/htdocs/symfony/vendor in /Applications/MAMP/htdocs/symfony/vendor/doctrine/orm/lib/Doctrine/ORM/ORMException.php on line 236

我没有得到的是'Unknown Entity namespace alias 'DSBlogBundle'在开发环境中完全"已知".有谁知道我错过了什么？任何帮助深表感谢!谢谢!