Web Form Builder Tutorial

I would like to have a go at building a 'Wufoo' type form builder. I have seen a few, and understand the logic behind creating it with the aid of javascript. However saving those form preferences for a returning user seems more complex for me, I was wondering i开发者_如何学编程f anywone has seen any examples/turorials of this?

Thanks.

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I made an experimental JSON-based form generator. You describe your form using JSON and a bit of JavaScript code generates the form. You could then serialize and store the form data in a database (even as a text blob if you're lazy), then re-load it on the client and generate the form.

You're welcome to the code if it gives you any ideas. It's all there in the page source.

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ExtJS is building a tool to create forms. The prototypes look pretty nice, but they have not released the tool yet.