FAQ: Introduction to PHP Form Validation - Sanitizing for Back-end Storage

This community-built FAQ covers the “Sanitizing for Back-end Storage” exercise from the lesson “Introduction to PHP Form Validation”.

Paths and Courses
This exercise can be found in the following Codecademy content:

Learn PHP

FAQs on the exercise Sanitizing for Back-end Storage

There are currently no frequently asked questions associated with this exercise – that’s where you come in! You can contribute to this section by offering your own questions, answers, or clarifications on this exercise. Ask or answer a question by clicking reply (reply) below.

If you’ve had an “aha” moment about the concepts, formatting, syntax, or anything else with this exercise, consider sharing those insights! Teaching others and answering their questions is one of the best ways to learn and stay sharp.

Join the Discussion. Help a fellow learner on their journey.

Ask or answer a question about this exercise by clicking reply (reply) below!
You can also find further discussion and get answers to your questions over in #get-help.

Agree with a comment or answer? Like (like) to up-vote the contribution!

Need broader help or resources? Head to #get-help and #community:tips-and-resources. If you are wanting feedback or inspiration for a project, check out #project.

Looking for motivation to keep learning? Join our wider discussions in #community

Learn more about how to use this guide.

Found a bug? Report it online, or post in #community:Codecademy-Bug-Reporting

Have a question about your account or billing? Reach out to our customer support team!

None of the above? Find out where to ask other questions here!

Hi there,
I’m a bit confused about structure of the pattern in the example as well as in the instructions.
It comes like this: preg_replace("/[^0-9]/", “”, $number);

Why should one use the forward slashes here? They were not necassary before, as far as I remember. And when I dont use them (just “[^0-9]”), then it seems to work just as fine.

Thanks for any help! :slight_smile:

Welcome to the forums, @java8805287390.

The forward slashes denote the RegularExpression data type. It helps to parse it out of the string object. Regexs are not strings. We also need the slashes if we wish to afix any flags such as g or i.

As for it working without the slashes, test this on a hard refresh before drawing any conclusions. Let us know what happens, either way.


Oh, I see. Thanks for the fast answer!
And of course, without the forward slashes it didnt work

1 Like

And you are wiser for knowing how to test before drawing any conclusions. One thing we learn when going down the PHP road is that mistakes are never forgiven. One minor slip-up and the response document is a white page with response code 500. Test, test and test again. Unlike JavaScript, PHP is not our friend.