How do I specify the amount whn using paypal "Pay now" button

I have my own shopping cart on my website, and when the user goes to pay, I just want them to press the "pay now" button and be taken to paypal an pay that amount. The amount however will vary from order to order, so I have looked into HTML variables in the paypal resource section, however adding does not 开发者_如何转开发seem to change the price, it seems to take the price that was specified when creating the button.

Any ideas?

Thanks

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I've had the same problem.

I noticed that MODx had solved it: http://modxcms.com/donate/

And i've implemented some of the same in my own donation form: http://webbies.dk/SudoSlider/donate/

Just copy the html of my input form (the CSS and images are my own, just copy it if you wan't), and adjust it to your needs.

Just set the input-type to hidden, if you don't want the user to edit the amount.