How to create custom helper in Magento 2

December 7, 2015 - Fire development, Magento 2

Magento 2 Development

First of all, you should create the app/code/Company1/Module1/composer.json file in order to create custom helper in Magento 2:

{
   "name": "company1/module-module1",
   "description": "",
   "require": {
       "php": "~5.5.0|~5.6.0|~7.0.0",
       "magento/framework": "100.0.*",
       "magento/module-ui": "100.0.*",
       "magento/module-config": "100.0.*",
       "magento/module-directory": "100.0.*"
   },
   "type": "magento2-module",
   "version": "100.0.0",
   "license": [
       "OSL-3.0",
       "AFL-3.0"
   ],
   "autoload": {
       "files": [ "registration.php" ],
       "psr-4": {
           "Company1\\Module1\\": ""
       }
   }
}

{

"name": "company1/module-module1",

"description": "",

"require": {

"php": "~5.5.0|~5.6.0|~7.0.0",

"magento/framework": "100.0.*",

"magento/module-ui": "100.0.*",

"magento/module-config": "100.0.*",

"magento/module-directory": "100.0.*"

"type": "magento2-module",

"version": "100.0.0",

"license": [

"OSL-3.0",

"AFL-3.0"

"autoload": {

"files": [ "registration.php" ],

"psr-4": {

"Company1\\Module1\\": ""

}

Then, create the app/code/Company1/Module1/registration.php file

\Magento\Framework\Component\ComponentRegistrar::register(
   \Magento\Framework\Component\ComponentRegistrar::MODULE,
   'Company1_Module1',
   __DIR__
);

\Magento\Framework\Component\ComponentRegistrar::register(

\Magento\Framework\Component\ComponentRegistrar::MODULE,

'Company1_Module1',

__DIR__

);

And make app/code/Company1/Module1/etc/module.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Module/etc/module.xsd">
   <module name="Company1_Module1" setup_version="2.0.0">
       <sequence>
           <module name="Magento_Directory"/>
       </sequence>
   </module>
</config>

<?xml version="1.0"?>

</sequence>

</module>

</config>

You’ve just created a module, and finally it is necessary to create a helper class inside the Helper folder. Create app/code/Company1/Module1/Helper/Data.php

namespace Company1\Module1\Helper;

class Data extends \Magento\Framework\App\Helper\AbstractHelper
{
   public function someMethod()
   {
       return 1;
   }
}

namespace Company1\Module1\Helper;

class Data extends \Magento\Framework\App\Helper\AbstractHelper

{

public function someMethod()

{

return 1;

}

Use it inside controller as follows:

$this->_objectManager->create('Company1\Module1\Helper\Data')->someMethod();

1	$this->_objectManager->create('Company1\Module1\Helper\Data')->someMethod();

Inside the block:

public function __construct(
       \Magento\Framework\View\Element\Template\Context $context,
       \Company1\Module1\Helper\Data $helper
       array $data = []
   ) {
       $this->helper = $helper
       parent::__construct($context, $data);
   }

public function __construct(

\Magento\Framework\View\Element\Template\Context $context,

\Company1\Module1\Helper\Data $helper

array $data = []

) {

$this->helper = $helper

parent::__construct($context, $data);

}

As you can see, $this->helper is an instance of Data. To overwrite classes, use preference.

app/code/Company1/Module1/etc/di.xml

<xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:ObjectManager/etc/config.xsd">
   <preference for="Magento\Directory\Helper\Data" type="Company1\Module1\Helper\Data" />
</config>