控制器是 CController 或者其子类的实例. 用户请求应用时,创建控制器。
控制器执行请求action,action通常引入必要的模型并提供恰当的视图。
最简单的action
仅仅是一个控制器类方法,此方法的名字以action
开始。
控制器有默认的action。用户请求不能指定哪一个action执行时,将执行默认的action。
缺省情况下,默认的action名为index
。可以通过设置CController::defaultAction改变默认的action。
下边是最小的控制器类。因此控制器未定义任何action,请求时会抛出异常。
class SiteController extends CController
{
}
控制器和actions通过ID标识的。控制器ID的格式: path/to/xyz
对应的类文件protected/controllers/path/to/XyzController.php
,
相应的 xyz
应该用实际的控制器名替换 (例如 post
对应 protected/controllers/PostController.php
).
Action ID与 action
前辍构成 action method。例如,控制器类包含一个 actionEdit
方法, 对应的 action ID就是 edit
。
注意: 在1.0.3版本之前, 控制器ID的格式是
path.to.xyz
而不是path/to/xyz
。
Users request for a particular controller and action in terms of route. A
route is formed by concatenating a controller ID and an action ID separated
by a slash. For example, the route post/edit
refers to PostController
and its edit
action. And by default, the URL
http://hostname/index.php?r=post/edit
would request for this controller
and action.
注意: By default, routes are case-sensitive. Since version 1.0.1, it is possible to make routes case-insensitive by setting CUrlManager::caseSensitive to be false in the application configuration. When in case-insensitive mode, make sure you follow the convention that directories containing controller class files are in lower case, and both controller map and action map are using keys in lower case.
Since version 1.0.3, an application can contain modules. The route for a controller action inside a module is in the format of moduleID/controllerID/actionID
. For more details, see the section about modules.
CWebApplication在处理一个新请求时,实例化一个控制器。程序通过控制器的ID,并按如下规则确定控制器类及控制器类所在位置
If CWebApplication::catchAllRequest is specified, a controller will be created based on this property, and the user-specified controller ID will be ignored. This is mainly used to put the application under maintenance mode and display a static notice page.
If the ID is found in CWebApplication::controllerMap, the corresponding controller configuration will be used to create the controller instance.
If the ID is in the format of 'path/to/xyz'
, the controller class
name is assumed to be XyzController
and the corresponding class file is
protected/controllers/path/to/XyzController.php
. For example, a controller
ID admin/user
would be resolved as the controller class UserController
and the class file protected/controllers/admin/UserController.php
.
If the class file does not exist, a 404 CHttpException will be raised.
In case when modules are used (available since version 1.0.3), the above process is slighly different. In particular, the application will check if the ID refers to a controller inside a module, and if so, the module instance will be created first followed by the controller instance.
As aforementioned, an action can be defined as a method whose name starts
with the word action
. A more advanced way is to define an action class
and ask the controller to instantiate it when requested. This allows
actions to be reused and thus introduces more reusability.
To define a new action class, do the following:
class UpdateAction extends CAction
{
public function run()
{
// place the action logic here
}
}
In order for the controller to be aware of this action, we override the actions() method of our controller class:
class PostController extends CController
{
public function actions()
{
return array(
'edit'=>'application.controllers.post.UpdateAction',
);
}
}
如上所示,使用路径别名application.controllers.post.UpdateAction
确定action类文件为protected/controllers/post/UpdateAction.php
.
Writing class-based actions, we can organize an application in a modular fashion以模块方式组织程序。例如,可以使用下边的目录结构组织控制器代码:
protected/ controllers/ PostController.php UserController.php post/ CreateAction.php ReadAction.php UpdateAction.php user/ CreateAction.php ListAction.php ProfileAction.php UpdateAction.php
Filter is a piece of code that is configured to be executed before and/or after a controller action executes. For example, an access control filter may be executed to ensure that the user is authenticated before executing the requested action; a performance filter may be used to measure the time spent in the action execution.
An action can have multiple filters. The filters are executed in the order that they appear in the filter list. A filter can prevent the execution of the action and the rest of the unexecuted filters.
A filter can be defined as a controller class method. The method name must
begin with filter
. For example, the existence of the
filterAccessControl
method defines a filter named accessControl
. The
filter method must be of the signature:
public function filterAccessControl($filterChain)
{
// call $filterChain->run() to continue filtering and action execution
}
where $filterChain
is an instance of CFilterChain which represents the
filter list associated with the requested action. Inside the filter method,
we can call $filterChain->run()
to continue filtering and action
execution.
A filter can also be an instance of CFilter or its child class. The following code defines a new filter class:
class PerformanceFilter extends CFilter
{
protected function preFilter($filterChain)
{
// logic being applied before the action is executed
return true; // false if the action should not be executed
}
protected function postFilter($filterChain)
{
// logic being applied after the action is executed
}
}
To apply filters to actions, we need to override the
CController::filters()
method. The method should return an array of
filter configurations. For example,
class PostController extends CController
{
......
public function filters()
{
return array(
'postOnly + edit, create',
array(
'application.filters.PerformanceFilter - edit, create',
'unit'=>'second',
),
);
}
}
The above code specifies two filters: postOnly
and PerformanceFilter
.
The postOnly
filter is method-based (the corresponding filter method is
defined in CController already); while the PerformanceFilter
filter is
object-based. The path alias application.filters.PerformanceFilter
specifies that the filter class file is
protected/filters/PerformanceFilter
. We use an array to configure
PerformanceFilter
so that it may be used to initialize the property
values of the filter object. Here the unit
property of
PerformanceFilter
will be initialized as 'second'
.
Using the plus and the minus operators, we can specify which actions the
filter should and should not be applied to. In the above, the postOnly
should be applied to the edit
and create
actions, while
PerformanceFilter
should be applied to all actions EXCEPT edit
and
create
. If neither plus nor minus appears in the filter configuration,
the filter will be applied to all actions.
Signup or Login in order to comment.