问题
I need to be able to change the product price when a custom checkbox is selected. I want to add $10.00 for engraving on one product and $20 to other products for engraving. I can't add it as a variant in Shopify because they handle inventory based off variants. I am using the Debut theme. I have the custom checkbox working in liquid and the textbox show/hide functioning.
回答1:
When someone checks the box for engraving, what they are doing is say, put a $10 product in my cart to go with this product. That $10 product is an engraving. You can use line item properties to glue the product with the engraving. When the customer clicks add to cart, you add both the product and the engraving to the cart, glued together with the line item properties. The reason? In the cart if they remove the product, you can also remove the engraving. Brilliant right! This pattern is common, and has been used to secure billions in sales... have fun!
来源：https://stackoverflow.com/questions/48852973/chang-the-product-price-when-custom-checkbox-is-selected-in-shopify