title: Introduction to a Controller
summary: A brief look at the definition of a Controller, creating actions and how to respond to requests.
# Introduction to Controllers
The following example is for a simple [api:Controller] class. When building off the SilverStripe Framework you will
subclass the base `Controller` class.
**mysite/code/controllers/TeamController.php**
:::php
allParams());
}
}
## Routing
We need to define the URL that this controller can be accessed on. In our case, the `TeamsController` should be visible
at http://yoursite.com/teams/ and the `players` custom action is at http://yoursite.com/team/players/.
If you're using the `cms` module with and dealing with `Page` objects then for your custom `Page Type` controllers you
would extend `ContentController` or `PageController`. You don't need to define the routes value as the `cms` handles
routing.
Make sure that after you have modified the `routes.yml` file, that you clear your SilverStripe caches using `?flush=1`.
**mysite/_config/routes.yml**
:::yml
---
Name: mysiteroutes
After: framework/routes#coreroutes
---
SilverStripe\Control\Director:
rules:
'teams//$Action/$ID/$Name': 'TeamController'
For more information about creating custom routes, see the [Routing](routing) documentation.
## Actions
Controllers respond by default to an `index` method. You don't need to define this method (as it's assumed) but you
can override the `index()` response to provide custom data back to the [Template and Views](../templates).
It is standard in SilverStripe for your controller actions to be `lowercasewithnospaces`
Action methods can return one of four main things:
* an array. In this case the values in the array are available in the templates and the controller completes as usual by returning a [api:HTTPResponse] with the body set to the current template.
* `HTML`. SilverStripe will wrap the `HTML` into a `HTTPResponse` and set the status code to 200.
* an [api:HTTPResponse] containing a manually defined `status code` and `body`.
* an [api:HTTPResponse_Exception]. A special type of response which indicates an error. By returning the exception, the execution pipeline can adapt and display any error handlers.
**mysite/code/controllers/TeamController.php**
:::php
/**
* Return some additional data to the current response that is waiting to go out, this makes $Title set to
* 'MyTeamName' and continues on with generating the response.
*/
public function index(HTTPRequest $request) {
return array(
'Title' => 'My Team Name'
);
}
/**
* We can manually create a response and return that to ignore any previous data.
*/
public function someaction(HTTPRequest $request) {
$this->setResponse(new HTTPResponse());
$this->getResponse()->setStatusCode(400);
$this->getResponse()->setBody('invalid');
return $this->getResponse();
}
/**
* Or, we can modify the response that is waiting to go out.
*/
public function anotheraction(HTTPRequest $request) {
$this->getResponse()->setStatusCode(400);
return $this->getResponse();
}
/**
* We can render HTML and leave SilverStripe to set the response code and body.
*/
public function htmlaction() {
return $this->customise(new ArrayData(array(
'Title' => 'HTML Action'
)))->renderWith('MyCustomTemplate');
}
/**
* We can send stuff to the browser which isn't HTML
*/
public function ajaxaction() {
$this->getResponse()->setBody(json_encode(array(
'json' => true
)));
$this->getResponse()->addHeader("Content-type", "application/json");
return $this->getResponse().
}
For more information on how a URL gets mapped to an action see the [Routing](routing) documentation.
## Security
See the [Access Controller](access_control) documentation.
## Templates
Controllers are automatically rendered with a template that makes their name. Our `TeamsController` would be rendered
with a `TeamsController.ss` template. Individual actions are rendered in `TeamsController_{actionname}.ss`.
If a template of that name does not exist, then SilverStripe will fall back to the `TeamsController.ss` then to
`Controller.ss`.
Controller actions can use `renderWith` to override this template selection process as in the previous example with
`htmlaction`. `MyCustomTemplate.ss` would be used rather than `TeamsController`.
For more information about templates, inheritance and how to render into views, See the
[Templates and Views](../templates) documentation.
## Link
Each controller should define a `Link()` method. This should be used to avoid hard coding your routing in views etc.
**mysite/code/controllers/TeamController.php**
:::php
public function Link($action = null) {
return Controller::join_links('teams', $action);
}
The [api:Controller::join_links()] is optional, but makes `Link()` more flexible by allowing an `$action` argument, and concatenates the path segments with slashes. The action should map to a method on your controller.
## Related Documentation
* [Execution Pipeline](../execution_pipeline)
* [Templates and Views](../templates)
## API Documentation
* [api:Controller]
* [api:Director]