Add Product to cart error: invalid request for adding product to quote

Question

I have a plugin and i want to add a product to the actual cart. This is my code:

          $productId = 2;
          $params = array(
                        'form_key' => $this->formKey->getFormKey(),
                        'product' => $productId, //product Id
                        'qty'   =>1 //quantity of product
                        'price' => 0
                    );
$_product = $this->product->load($productId);
$cart->addProduct($_product, $params);
$cart->save();

and i get the error: invalid request for adding product to quote. I try this:

          $productId = 2;
          $params = array(
                        'form_key' => $this->formKey->getFormKey(),
                        'product' => $productId, //product Id
                        'qty'   =>1, //quantity of product
                        'price' => 0
                    );
          //Load the product based on productID
          $request = new Varien_Object();
          $request->setData($params);
          $_product = $this->product->load($productId);
          $cart->addProduct($_product, $params);
          $cart->save();

But it crash without any error.

Can someone help me to add a product to cart?

Thank you in advance!

Answer 1

Please try using below code, it is controller file so update it accordingly :

<?php
namespace Test\Module\Controller\Cart;

class Test extends \Magento\Framework\App\Action\Action
{
    protected $_pageFactory;
    protected $formKey;
    protected $checkoutSession;
    protected $cart;

    public function __construct(
        \Magento\Framework\App\Action\Context $context,
        \Magento\Framework\Data\Form\FormKey $formKey,
        \Magento\Checkout\Model\Session $checkoutSession,
        \Magento\Checkout\Model\Cart $cart,
        \Magento\Framework\View\Result\PageFactory $pageFactory
    ){
        $this->_pageFactory = $pageFactory;
        $this->formKey = $formKey;
        $this->checkoutSession = $checkoutSession;
        $this->cart = $cart;
        return parent::__construct($context);
    }

    public function execute()
    {
            $resultPage = $this->_pageFactory->create();
            $params = array(
                'form_key' => $this->formKey->getFormKey(),
                'product' =>146,
                'qty'   =>1,                
            );
            $this->_redirect("checkout/cart/add/form_key/", $params);
    }
}