How to set quantity of cart as 0 programmatically

Question

I want to programm Magento in such a way that the quantity of cart displays zero even if the product is Added into the cart. Initially there will be one product into cart but it hasn't to be displayed on the top menu cart link

I have used following code but I don't get enough response.

Mage::getModel('checkout/cart')->getQuote()->setItemsQty(0);

Answer 1

Clear shopping cart

foreach (Mage::getSingleton('checkout/session')->getQuote()->getItemsCollection() as $item ) {
    Mage::getSingleton('checkout/cart')->removeItem($item->getId())->save();
}

If you want to Clear entire session

Mage::getSingleton('checkout/session')->clear();

Answer 2

If you have a large number of customers quotes then deleting them by using loop might be time and resource consuming. You can clear/delete all customers cart items (all active sales quotes) by using the following SQL query:

DELETE FROM sales_flat_quote WHERE is_active = 1;

is_active = 0 means those quotes have been converted into orders, i.e. customer has placed order for those quotes.

is_active = 1 means quotes that have not been ordered, i.e. quotes present in the shopping cart of customers

Running this query will automatically delete related rows (quote items) from sales_flat_quote_item table through foreign key constraint.

Answer 3

Below are the list of options and all options are working for my case.

1.Mage::getSingleton('checkout/session')->clear();

2.Mage::getSingleton('checkout/cart')->truncate();

3.$quote = Mage::getSingleton('checkout/session')->getQuote(); 
$quote->delete();

4.Mage::getSingleton('checkout/cart')->truncate()->save();

5.Mage::getSingleton('checkout/session')->setCartWasUpdated(true);

6.foreach( Mage::getSingleton('checkout/session')->getQuote()->getItemsCollection() as $item ){
    Mage::getSingleton('checkout/cart')->removeItem( $item->getId() )->save();
}

7.$cartHelper = Mage::helper('checkout/cart');
    $items = $cartHelper->getCart()->getItems();       
    foreach ($items as $item)
    {
            $itemId = $item->getItemId();
            $cartHelper->getCart()->removeItem($itemId)->save();
    }

8.$quote = Mage::getSingleton('checkout/session')->getQuote();
$item = $quote->getItemByProduct($product);
$quote->removeItem($item->getId());

9.$quote->removeAllItems();