This section contains a step-by-step guide to creating an application that captures a single field which conforms to a certain regular expression. This could be a date, some code, etc. The more specific the data is, the easier it would be to capture it. In this guide we will capture an alphanumeric code, for example: X6Yz647a.
An alphanumeric code needs no additional check besides the regular expression. However, there is the option of implementing a block which would perform additional validation after the data has passed the regular expression check, for example, calculate the field's checksum (see the setPredicateBlock: method).
See the description of classes and methods in the API Reference section.