Validation is a technique to ensure that input is secure before using it in your code.
When validating data, you are verifying that it corresponds to what the program needs. This only works if you have a list of criteria that you can check to determine that the data is valid.
In this article, we’re going to look at:
- How to validate using whitelisting.
- How to validate using data qualifications, including how to choose the right qualifications.
- What validation functions WordPress offers.
- What validation functions that the PHP language offers.