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Version: 20

About class functions

This section describes the built-in 4D class functions as well as the associated constructor commands. 4D class functions and properties are available through class instance objects.

  • functions must be called on instances with the () operator. For example, collection.sort().
  • properties are accessed without parentheses, for example file.creationTime. You can also use the [] syntax, for example file["creationTime"].
  • commands can be called independantly, with or without parameters. For example Folder(fk database folder).

Writing conventions

The following conventions are used in the function syntax:

  • the { } characters (braces) indicate optional parameters. For example, .delete( { option : Integer } ) means that the option parameter may be omitted when calling the function.
  • the { ; ...param } notation indicates an unlimited number of parameters. For example, .concat( value : any { ;...valueN } ) : Collection means that an unlimited number of values of any type can be passed to the function.
  • the any keyword is used for parameters that can be of any type that can be stored within attributes (number, text, boolean, date, time, object, collection...).