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Tech Tip: How to create DataClass-associated classes
PRODUCT: 4D | VERSION: 19 | PLATFORM: Mac & Win
Published On: April 25, 2022

DataClasses are essentially the ORDA equivalents of tables. For instance, given an Employee table, there exists an Employee DataClass. For each DataClass, there are 3 associated classes:

  • DataClass Class

  • Entity Class

  • EntitySelection Class

  • To create these associated classes, one can create the classes from scratch by following a naming convention and adding “Class extends ____” at the start of their class method. For example, given the Employee DataClass:

  • DataClass Class: “Employee” & “Class extends DataClass”

  • Entity Class: “EmployeeEntity” & “Class extends Entity”

  • EntitySelection Class: “EmployeeSelection” & “Class extends EntitySelection”

  • Alternatively, the DataClass-associated classes can be generated by clicking the settings (cog) icon in Explorer > Methods, then checking “Show all data classes”.



    Initially, the classes will be greyed out, until double-clicked to be created.



    Once created, functions can be added to the class to create object methods for the DataClass itself, the DataClass’s entities, and the DataClass’s entity selections, respectively.