Hello learners, Welcome to Learn Sitecore. In this blog we will see how to create custom field validation rule for a field of an item. Providing a field validation rule to a field provides a great flexibility to the developers as well as good experience for content authors. By adding it choosing an invalid date by content author and showing it in the website can be eliminated at the first step itself. It is recommended to use field validations for different fields based on the business requirements. To implement a custom field rule validation, navigate to /sitecore/system/Settings/Validation Rules/Field Rules and insert a validation rule. After that fill the data into Text and Data sections as follows. Text Section Data Section In the Type field add the data as class reference name, assembly name. Now create a class file that extends the standard validator class. Write the logic as per your requirement in the Evaluate function. For the instance I have added a sample code wh...