Q:

How to get helper instance on Magento 2.1?

I tested all methods that I found that were reported here all about Magento 2.0, but seems like Magento 2.1 is different, how can I do that?

A:

Here is an example of using the Magento\Catalog\Helper\Product helper class by using dependency injection,
private $productHelper;

public function __construct(
    \Magento\Catalog\Helper\Product $productHelper
){
    $this->productHelper = $productHelper;
}

public function myFunction()
{
    $this->productHelper->doSomething();
}

