Cross-field validation, also known as multi-field validation, is a process in programming where the values of multiple fields are checked together to ensure they meet certain criteria. It’s used when data entered into one field affects the requirements for another. For instance, if a user enters their age as 17, and then tries to register for an activity that requires them to be at least 18, cross-field validation would prevent this from happening by checking both fields against each other. Another example could be validating date ranges; start date should not exceed end date. This method ensures data integrity and improves user experience by preventing incorrect or illogical data entries.
