getQty（）在magento 1.9中给出致命错误

Question

I am trying to get the collection based on product and quote Id using,

$quotecollection = Mage::getModel('sales/quote_item')->getCollection()->addFieldToFilter('quote_id',$quoteId)->addFieldToFilter('product_id',$product_id);

$quotecollectionaArr =  $quotecollection->getData();
echo $quotecollection->getQty();

which gives the following error

Fatal error: Call to undefined method Mage_Sales_Model_Resource_Quote_Item_Collection::getQty() in C:\xampp\htdocs....

Please help.

Answer 1

You should use getFirstItem()

  $quotecollection = Mage::getModel('sales/quote_item')->getCollection()->addFieldToFilter('quote_id',$quoteId)->addFieldToFilter('product_id',$product_id)->getFirstItem();
  echo $quotecollection->getQty();