Validate form input with regex (no jquery)

Question

I'm getting a lot of spam om my websites where I have a couple of email/contact forms.

The forms are all validated/submitted inline with jQuery/ajax.

However, spam bots skip javascript so I want to validate the form natively too.

I don't want to use a (hidden) CAPTCHA.

EE/CI can validate emails and numbers etc. But I have a phone number field for example and I don't want to force users to use a specific pattern 000-000-000 etc. I just want to allow only 0-9 spaces and dashes and (). At the moment spam bots put anything there.

Also, I have a name field which spam bots use to put email addresses in. So I would like to disallow the @ sign and other symbols that no one uses in their name.

Also I don't want to even accept html tags or common spam strings like "

How would I do this without javascript?

Answer 1

You couldn't have such validations via the freeform tags. You will need to develop an extension with the hook freeform_module_validate_begin. Within the hooked function you can validate the user inputs and prepare the $error array.

You can take a reference from here: http://www.solspace.com/docs/freeform/extension_hooks/#freeform_module_validate_begin

Answer 2

Freeform 4 allows specifying different types of text inputs, including numbers, when creating text fields: http://www.solspace.com/docs/freeform/default_fieldtypes/#text_field_content_type

Input failing the requirements will be validated negative.