Such complex processing may include the testing of conditional constraints for an entire complex data object or set of process operations within a system.
Data validation rules may be defined, designed and deployed, for example: Definition and design contexts: Data that does not conform to these rules will negatively affect business process execution.
Therefore, data validation should start with business process definition and set of business rules within this process.
For example, an experienced user may enter a well-formed string that matches the specification for a valid e-mail address, as defined in RFC 5322 but that well-formed string might not actually correspond to a resolvable domain connected to an active e-mail account.
Structured validation allows for the combination of any of various basic data type validation steps, along with more complex processing.
(See also data type checks below)Checks for missing records.
Numerical fields may be added together for all records in a batch.
For example, many database systems allow the specification of the following l (plus, minus, and parentheses).
A more sophisticated data validation routine would check to see the user had entered a valid country code, i.e., that the number of digits entered matched the convention for the country or area specified.
The following code example uses the derived class Text Box and validates an e-mail address that the user enters.
If the e-mail address is not in the standard format (containing "@" and "."), the validation fails, an Error Provider icon is displayed, and the event is canceled.
Doing so can cause your application or the operating system to stop responding.