How to use Regular Expression

Have you ever needed to validate input from users to ensure it matches a specific pattern or set of rules? That's where regular expressions, or regex for short, come in handy! A regex is a powerful tool used to match and manipulate text based on specific patterns or rules. Know more!

How do you use regular expressions in BlockSurvey?

If you're using BlockSurvey to create a form, you can easily add regex validation to certain question types, such as email. Here's how:

1. Select the question type in the builder.
2. Next, navigate to the Validation tab for the email question.
3. You can then add your regex pattern along with a custom error message that will be displayed to the user if their input does not match the pattern.
4. Once you've published your changes, BlockSurvey will validate user input against your regex pattern and display the error message if necessary.

For example, let's say you want to ensure that a respondent's email address is a Gmail address. You can add the following regex pattern under the Validation tab:

^\w+([.-]?\w+)*@gmail.com$

This pattern will match any input that contains a valid Gmail email address. If a respondent enters an email address that does not match this pattern, they will see the error message you specified under Validation.

Give it a try! Experiment with different patterns and see how regex can improve the quality of your data.