Property definitions

Model properties are defined using PropertyInfo class. A general property definition looks like that:

var property = new Property(name, type, flags, getter, setter);

Arguments name and type are required. Argument name is a string, and it defines the name of the property. Argument type is either a DataType member or another model's type:

var price = new Property('price', DataType.Decimal);
var customer = new Property('customer', Customer);

The following data types are supported out of the box: Boolean, Text, Email, Integer, Decimal, Enum and DateTime. Custom data types can be created as well. See Data types page for details.

Properties representing child models or collections are read-only ones to prevent their unintended deletions.

Arguments flags, getter and setter can be used when type is a DataType member. Argument flags is a combination of PropertyFlag values:

• none
  The default value. The property is a normal read-write property.
• readOnly
  The property can be read but cannot be written, i.e. it has getter only. This flag is ignored for read-only business objects.
• key
  The property is a key element of the business object.
• parentKey
  The property holds the key element of the parent business object.
• onCtoOnly
  The property is not cloned onto the data transfer object, i.e. it is not persisted. It usually marks a calculated property that is required by the client application.
• onDtoOnly
  The property is not cloned onto the client transfer object, but it is required for the business logic.

Keys are internally used in business objects as well. In remove actions keys are passed as filter arguments to data access objects. Keys are also used in child collections to identify collection items when a business object is rebuilt from the client transfer object.

Some examples:

var orderItemKey = new Property('orderItemKey', DataType.Integer, F.key | F.readOnly);
var orderKey = new Property('orderKey', DataType.Integer, F.parentKey | F.readOnly);
var fullName = new Property('fullName', DataType.Text, F.onCtoOnly | F.readOnly);
var secret = new Property('secret', DataType.Text, F.onDtoOnly);

Argument getter is a function that replaces the internal getter function that is equivalent to the following custom getter:

function getFirstName (ctx) {
  return ctx.getValue('firstName');
}

E.g. a fullName property can be defined in this way:

function getFullName (ctx) {
  return ctx.getValue('firstName') + ' ' + ctx.getValue('lastName');
}
var firstName = new Property('firstName', DataType.Text);
var lastName = new Property('lastName', DataType.Text);
var fullName = new Property('fullName', DataType.Text, F.onCtoOnly | F.readOnly, getFullName);

Similarly, argument setter is a function that replaces the internal setter function. Custom setter is ignored for read-only properties. The internal setter function is equivalent to the following custom one:

function setLastName (ctx, value) {
  ctx.setValue('lastName', value);
}

E.g. firstName and lastName properties can be defined in this way:

function setFullName (ctx, value) {
  ctx.setValue('fullName', value);
  var names = value.split(' ');
  ctx.setValue('firstName', name[0]);
  ctx.setValue('lastName', name[1]);
}
var firstName = new Property('firstName', DataType.Text, F.onDtoOnly | F.readOnly);
var lastName = new Property('lastName', DataType.Text, F.onDtoOnly | F.readOnly);
var fullName = new Property('fullName', DataType.Text, F.onCtoOnly, null, setFullName);

The context argument is a PropertyContext object that has the following members to use:

• primaryProperty
  A read-only property that returns a PropertyInfo object that contains the definition of the property itself.
• properties
  A read-only property that returns an array of PropertyInfo objects that contain the definitions of all properties.
• getValue(propertyName)
  The method returns the value of the property determined by the given name.
• setValue(propertyName, value)
  The method sets the value of the property determined by the given name.