entity.fromObject( )

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4D v19

4D Language Reference

ORDA - Entity

entity.fromObject( )

Description

The entity.fromObject( ) method fills an entity with the object content.

Note: This method modifies the original entity.

The mapping between the object and the entity is done on the attribute names:

If a property of the object does not exist in the dataclass, it is ignored.
Data types must be equivalent. If there is a type mismatch between the object and dataclass, 4D tries to convert the data whenever possible (see RELATE MANY), otherwise the attribute is left untouched.
The primary key can be given as is or with a "__KEY" property (filled with the primary key value). If it does not already exist in the dataclass, the entity is created with the given value when entity.save( ) is called. If the primary key is not given, the entity is created and the primary key value is assigned with respect to database rules. The auto-increment is only computed if the primary key is null.

object can handle a related entity under the following conditions:

object contains the foreign key itself, or
object contains a property object with the same name as the related entity, containing a single property named "__KEY".
if the related entity does not exist, it is ignored.

Example

With the following $o object:

{
    "firstName": "Mary",
    "lastName": "Smith",
    "salary": 36500,
    "birthDate": "1958-10-27T00:00:00.000Z",
    "woman": true,
    "managerID": 411,// relatedEntity given with PK
    "employerID": 20 // relatedEntity given with PK
}

The following code will create an entity with manager and employer related entities.

 C_OBJECT($o)

 $entity:=ds.Emp.new()

 $entity.fromObject($o)

 $entity.save()

You could also use a related entity given as an object:

{
    "firstName": "Marie",
    "lastName": "Lechat",
    "salary": 68400,
    "birthDate": "1971-09-03T00:00:00.000Z",
    "woman": false,
    "employer": {// relatedEntity given as an object
        "__KEY": "21"
    },
    "manager": {// relatedEntity given as an object
        "__KEY": "411"
    }
}