Codeigniter 2.x项目提示 A PHP Error was encountered Severity: Notice Message: Only variable references should be returned by reference Filename: core/Common.php Line Number: 257 解决方法 进入system/core,修改Common.php 257行 修改前 return $_config[0] =& $config; 修改后 $_config[0] =& $config; return $_config[0];