Yii2中系统定义的常用路径别名，如果获取web的url

下面这些别名都是在Yii2里面系统定义的，可以直接拿来就用

• "@yii" =>
  
  •       "@yii/swiftmailer" => string "C:wampwwwadvancedvendor/yiisoft/yii2-swiftmailer" (length=52)
  •       "@yii/gii" => string "C:wampwwwadvancedvendor/yiisoft/yii2-gii" (length=44)
  •       "@yii/faker" => string "C:wampwwwadvancedvendor/yiisoft/yii2-faker" (length=46)
  •       "@yii/debug" => string "C:wampwwwadvancedvendor/yiisoft/yii2-debug" (length=46)
  •       "@yii/codeception" => string "C:wampwwwadvancedvendor/yiisoft/yii2-codeception" (length=52)
  •       "@yii/bootstrap" => string "C:wampwwwadvancedvendor/yiisoft/yii2-bootstrap" (length=50)
  •       "@yii" => string "C:wampwwwadvancedvendoryiisoftyii2" (length=40)
    
•   "@app" => string "C:wampwwwadvancedfrontend" (length=29)
•   "@vendor" => string "C:wampwwwadvanced/vendor" (length=27)
•   "@bower" => string "C:wampwwwadvanced/vendorower" (length=33)
•   "@npm" => string "C:wampwwwadvanced/vendor pm" (length=31)
•   "@runtime" => string "C:wampwwwadvancedfrontend untime" (length=37)
•   "@webroot" => string "C:/wamp/www/advanced/frontend/web" (length=33)
•   "@web" => string "/advanced/frontend/web" (length=22)
  

其中最常用的别名有

• @app
• @vendor
• @runtime
• @webroot
• @web
  

而且可以看到除了@web别名是url外，其它的都是物理路径

来源：http://yiifans.com/forum.php?mod=viewthread&tid=9578&extra=