Html forms - checkbox - how to add string to search?

I have a html form that searches an online store, right now I’m using radio buttons to search for items 10-30% off. Now I’m wanting to add a checkbox to also search for items that offer free shipping. How do I add a checkbox to the form which will add to the existing % off string?

Thanks in advance.

I keep playing with the code and I don’t think it’s going to be possible.

Such as adding the following checkbox:

<input type="checkbox" value="ship0-" name="search" id="shipping">

Then performing a search for Xbox that’s 10% off and free shipping results in the following string:[COLOR="#FF0000"]search=10off[/COLOR]&[COLOR="#0000CD"]search=ship0[/COLOR]

The Red and Blue lines need to be merged in order for it to work, like:

I realise I’m very late, but what you’re asking is not possible in HTML only. You’d need either some Javascript on the client side, or some server side processing (which would be preferred over client side).

The problem is your api call. The “&” separates each variable / value pair. You can’t smash them all together like that. I’m assuming your using your querying a third party api and not querying your own database?