Generate link in cakephp using Html helper - html

Question

I am trying to simply create a link in my controller using the Html helper and I get the below error although I have added the necessary helper:
Call to a member function link() on a non-object
public $helpers = array('Html', 'Form');
$url = $this->Html->link(
'',
'http://www.example.com/',
['class' => 'button', 'target' => '_blank']
);

Answer 1

You can use Helpers inside your view files but not inside your controller
http://book.cakephp.org/2.0/en/views/helpers.html#using-helpers.
For example in your index.ctp
echo $this->Html->link(
__('My link'),
'http://www.example.com/',
array('class' => 'button', 'target' => '_blank')
);
Enabling Html Helper in your Controller is same as in your code.
class ExamplesController extends AppController {
$helpers = array('Html', 'Form');
public function index() {
//
}
}

Answer 2

This is a good question. I think your a little confused with MVC and the separation of concerns the design pattern provides. Take a look (again) at how CakePHP implements MVC: http://book.cakephp.org/2.0/en/cakephp-overview/understanding-model-view-controller.html.
The important thing to remember is that your controllers should never be concerned with creating anchor tags. That's the job of your views. Since helpers are a way to keep your views DRY (Don't Repeat Yourself) having one thats sole responsibility is to create HTML elements is really handy. Views are dependent on controllers to determine what variables are set, what their value is, as well as what helpers are loaded. For more information on Helpers as well as components for controllers and behaviors for models check out http://book.cakephp.org/2.0/en/getting-started/cakephp-structure.html as well as each of their individual documentation pages:
Helpers - http://book.cakephp.org/2.0/en/views/helpers.html
Components - http://book.cakephp.org/2.0/en/controllers/components.html,
Behaviors - http://book.cakephp.org/2.0/en/models/behaviors.html.
Now that you have a better understanding of MVC, let's take a look at your specific issue. Your wanting to create a link in your controller. I assume it might be dynamic depending on some other variables so I'm going to roll with that.
A common problem that you can solve you want to show a login/logout link depending on if the user is already logged in.
In app/Controller/ExampleController.php
class ExampleController extends AppController {
public $components = array('Auth');
public $helpers = array('Html', 'Form');
public function beforeRender() {
parent::beforeRender();
//if Auth::user() returns `null` the user is not logged in.
if ($this->Auth->user() != null) {
$logInOutText = 'Log out';
$logInOutUrl = array('controller' => 'users', 'action' => 'login');
} else {
$logInOutText = 'Log in';
$logInOutUrl = array('controller' => 'users', 'action' => 'logout');
}
$this->set(compact('logInOutText', 'logInOutUrl'));
}
}
You can then so something simple in your view. In this case I'm choosing the default layout because I want the links in every rendered page. app/View/Layouts/default.ctp
<!-- More HTML above -->
<?php
// "Html" in `$this->Html` refers to our HtmlHelper. Note that in a view file
// like a `.ctp`, `$this` referes to the View object, while above in the
// controller `$this` refers to the Controller object. In the case
// `$this->Html`, "Html" would refer to a component. The same goes for Models
// and behaviors.
echo $this->Html->link($logInOutText, $logInOutUrl); // Easy!
?>
<!-- More HTML below -->
I hope this helps. I know it's a lot to put together at one time.

Answer 3

Though it is not good practice. However still if you need this you can use following code in your controller
App::uses('HtmlHelper', 'View/Helper');
$yourTmpHtmlHelper = new HtmlHelper(new View());
$url=$yourTmpHtmlHelper->link(
'',
'http://www.example.com/',
['class' => 'button', 'target' => '_blank']
);
This should work for cakephp 2.*
Thanks