Custom step between product page and shopping cart

Question

I need to develop a custom step between the Magento product detail page and the shopping cart. If the user clicks on 'Add to cart' the user should be redirected to a new custom form page to enter his/her birthday first. After submitting the birthday data the product should be added to the shopping cart as normal. The birthday data fields should be saved in the quote- and if the user goes to checkout also in the order-model.

I'm new to Magento development so it would be great if somebody could give me some rough hints or guideline where to start and how to plug in.

Thanks a lot in advance!

Answer 1

First way:

1. You'll have to override app/code/core/Mage/Catalog/Block/Product/List.php block and create a new function which will load your custom form which use to insert birth day etc.
2. Then in the template file app/design/frontend/base/default/template/catalog/product/list.phtml around line 61 and line 103 invoke your custom function instead of getAddToCartUrl($_product) function in the onclick event of Add to Cart button
3. Make sure to invoke getAddToCartUrl($_product) function inside your custom function after submitting your custom form.

Second way:

1. Write an event/observer to inject your custom form when user click the Add to Cart button. You can try with this event 'checkout_cart_save_before'.

Note: I didn't test this event. If it didn't work refer here for achieve the relevant one http://www.nicksays.co.uk/magento-events-cheat-sheet-1-7/