4D v15.4
Structure of 4D language objects
- 4D Language Reference
-
- Objects (Language)
-
- Structure of 4D language objects
- OB CopyUpd
- OB GET ARRAYUpd
- OB GET PROPERTY NAMESUpd
- OB Get typeUpd
- OB GetUpd
- OB Is definedUpd
- OB Is emptyUpd
- OB REMOVEUpd
- OB SET ARRAYUpd
- OB SET NULLUpd
- OB SETUpd
Structure of 4D language objects
The commands of the Objects (Language) theme create and work with data in object form. This extends the exchange opportunities between 4D and any application that supports structured data.
All the commands in this theme support the following 4D objects:
- Object variables or object arrays created and initialized using the C_OBJECT ("Compiler" theme) or ARRAY OBJECT ("Arrays" theme) commands.
- Object fields from the 4D database (see 4D field types).
The structure of "native" 4D objects is based on the classic principle of "property/value" pairs. The syntax of these objects is based on JSON notation, but does not follow it completely.
Note: To work with JSON objects, you must use the commands found in the "JSON" theme.
- An attribute name is always a text, for example "Name".
- An attribute value can be one of the following types:
- number (Real, Integer, etc.)
- text
- array (text, real, longint, integer, Boolean, object, pointer)
- null
- Boolean
- date (format "YYYY-MM-DDTHH:mm:ss.SSSZ")
- object (objects can be nested on several levels)
- object variables and arrays also support pointers (stored as such, evaluated using the JSON Stringify command or when copying).
Warning: Keep in mind that attribute names differentiate between upper and lower case.
Product: 4D
Theme: Objects (Language)
Modified: 4D v15
4D Language Reference ( 4D v15)
4D Language Reference ( 4D v15.4)
4D Language Reference ( 4D v15.3)
