# Object ## Overview The Object type is used to store various keyed collections and more complex entities.\ Nearly all objects in JavaScript are instances of Object. For more information see: [Object (MDN)](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object). ## Methods Summarized | Type | Name | Summary | | ---------------------------------------------------------- | ------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [assign(target, sources)](#assign-target-sources) | Copy the values of all enumerable own properties from one or more source objects to a target object. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [create(object)](#create-object) | Creates a new object, using an existing object to provide the newly created object's prototype. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [create(object, properties)](#create-object-properties) | Creates a new object, using an existing object to provide the newly created object's prototype and properties. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [defineProperties(object, properties)](#defineproperties-object-properties) | Defines new or modifies existing properties directly on an object, returning the object. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [defineProperty(object, property, descriptor)](#defineproperty-object-property-descriptor) | Allows a precise addition to or modification of a property on an object. | | [Array](/reference/servoycore/dev-api/js-lib/array.md) | [entries(object1)](#entries-object1) | Returns an array whose elements are arrays corresponding to the enumerable string-keyed property key-value pairs found directly upon object. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [freeze(object)](#freeze-object) | Freezes an object: that is, prevents new properties from being added to it; prevents existing properties from being removed; and prevents existing properties, or their enumerability, configurability, or writability, from being changed. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [fromEntries(entries)](#fromentries-entries) | Transforms a list of key-value pairs into an object | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [getOwnPropertyDescriptor(object, property)](#getownpropertydescriptor-object-property) | Permits examination of the precise description of a property. | | [Array](/reference/servoycore/dev-api/js-lib/array.md) | [getOwnPropertyNames(object)](#getownpropertynames-object) | Returns an array of all properties (including non-enumerable properties) found directly upon a given object. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [getPrototypeOf(object)](#getprototypeof-object) | Returns the prototype of the specified object. | | [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) | [hasOwnProperty(prop)](#hasownproperty-prop) | Determine whether the object has the specified property as its own property (as opposed to inheriting it). | | [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) | [is(value1, value2)](#is-value1-value2) | Determines whether two values are the same value. | | [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) | [isExtensible(object)](#isextensible-object) | Determines if an object is extensible (whether it can have new properties added to it). | | [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) | [isFrozen(object)](#isfrozen-object) | Determines if an object is frozen. | | [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) | [isPrototypeOf(object)](#isprototypeof-object) | Checks if an object exists in another object's prototype chain. | | [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) | [isSealed(object)](#issealed-object) | Determines if an object is sealed. | | [Array](/reference/servoycore/dev-api/js-lib/array.md) | [keys(object)](#keys-object) | Returns an array of all own enumerable properties found upon a given object, in the same order as that provided by a for-in loop (the difference being that a for-in loop enumerates properties in the prototype chain as well). | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [preventExtensions(object)](#preventextensions-object) | Prevents new properties from ever being added to an object (i. | | [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) | [propertyIsEnumerable(prop)](#propertyisenumerable-prop) | Indicates whether the specified property is enumerable. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [seal(object)](#seal-object) | Seals an object, preventing new properties from being added to it and marking all existing properties as non-configurable. | | void | [setPrototypeOf(obj, prototype)](#setprototypeof-obj-prototype) | Sets the prototype of a specified object to another object or null. | | [String](/reference/servoycore/dev-api/js-lib/string.md) | [toLocaleString()](#tolocalestring) | Returns a string representing the object. | | [String](/reference/servoycore/dev-api/js-lib/string.md) | [toString()](#tostring) | Returns a string representing the specified object. | | [Object](/reference/servoycore/dev-api/js-lib/object.md) | [valueOf()](#valueof) | Returns the primitive value of the specified object. | | [Array](/reference/servoycore/dev-api/js-lib/array.md) | [values(object1)](#values-object1) | Returns an array whose elements are strings corresponding to the enumerable string-keyed property values found directly upon object. | ## Methods Detailed ### assign(target, sources) Copy the values of all enumerable own properties from one or more source objects to a target object. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **target** The target object. * [Array](/reference/servoycore/dev-api/js-lib/array.md) **sources** The source object(s). **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) The target object. **Sample** ```js var object1 = { a: 1, b: 2, c: 3}; var object2 = Object.assign({c: 4, d: 5}, object1); application.output(object2.c, object2.d); ``` ### create(object) Creates a new object, using an existing object to provide the newly created object's prototype. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object which should be the prototype of the newly-created object. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) A new object with the specified prototype object. **Sample** ```js const person = { isHuman: false, printIntroduction: function () { application.output("My name is " + this.name + ". Am I human? " + this.isHuman); } }; var me = Object.create(person); me.name = "Matthew"; // "name" is a property set on "me", but not on "person" me.isHuman = true; // inherited properties can be overwritten me.printIntroduction(); // expected output: "My name is Matthew. Am I human? true" ``` ### create(object, properties) Creates a new object, using an existing object to provide the newly created object's prototype and properties. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object which should be the prototype of the newly-created object. * [Object](/reference/servoycore/dev-api/js-lib/object.md) **properties** ; **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) A new object with the specified prototype object. **Sample** ```js var o = Object.create({}, { p: { value: 42 } }); application.output(o.p); ``` ### defineProperties(object, properties) Defines new or modifies existing properties directly on an object, returning the object. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object on which to define or modify properties. * [Object](/reference/servoycore/dev-api/js-lib/object.md) **properties** An object whose own enumerable properties constitute descriptors for the properties to be defined or modified.\ Descriptors have the following keys:\ configurable - true if and only if the type of this property descriptor may be changed and if the property may be deleted\ from the corresponding object. Defaults to false.\ enumerable - true if and only if this property shows up during enumeration of the properties on the corresponding object.\ Defaults to false.\ value - The value associated with the property. Can be any valid JavaScript value (number, object, function, etc).\ Defaults to undefined.\ writable - true if and only if the value associated with the property may be changed with an assignment operator.\ Defaults to false.\ get - A function which serves as a getter for the property, or undefined if there is no getter. The function return will\ be used as the value of property. Defaults to undefined.\ set - A function which serves as a setter for the property, or undefined if there is no setter. The function will receive\ as only argument the new value being assigned to the property. Defaults to undefined. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) The object that was passed to the function. **Sample** ```js const object1 = {}; Object.defineProperties(object1, {property1: {value: 42, writable: true}, property2: {}}); application.output(object1.property1); ``` ### defineProperty(object, property, descriptor) Allows a precise addition to or modification of a property on an object. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object on which to define or modify properties. * [Object](/reference/servoycore/dev-api/js-lib/object.md) **property** The name of the property to be defined or modified. * [Object](/reference/servoycore/dev-api/js-lib/object.md) **descriptor** The descriptor for the property being defined or modified. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) The object that was passed to the function. **Sample** ```js const object1 = {}; Object.defineProperty(object1, 'property1', {value: 42, writable: false}); application.output(object1.property1); ``` ### entries(object1) Returns an array whose elements are arrays corresponding to the enumerable string-keyed property key-value pairs found directly upon object. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object1** An object. **Returns:** [Array](/reference/servoycore/dev-api/js-lib/array.md) An array of the given object's own enumerable string-keyed property key-value pairs. Each key-value pair is an array with two elements: the first element is the property key (which is always a string), and the second element is the property value. **Sample** ```js const object1 = { a: 'somestring', b: 42, c: false}; application.output(Object.entries(object1)); ``` ### freeze(object) Freezes an object: that is, prevents new properties from being added to it; prevents existing properties from being removed; and prevents existing properties, or their enumerability, configurability, or writability, from being changed. In essence the object is made effectively immutable. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object to freeze. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) The object that was passed to the function. **Sample** ```js const object1 = { property1: 42 }; const object2 = Object.freeze(object1); object2.property1 = 33; application.output(object2.property1); //expected result is 42 ``` ### fromEntries(entries) Transforms a list of key-value pairs into an object **Parameters** * [Array](/reference/servoycore/dev-api/js-lib/array.md) **entries** A list of objects. Each object is an array with two values, first value is the key second one is the value. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) A new object whose properties are given by the entries of the array. **Sample** ```js application.output(Object.fromEntries(entries)); ``` ### getOwnPropertyDescriptor(object, property) Permits examination of the precise description of a property. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object in which to look for the property. * [Object](/reference/servoycore/dev-api/js-lib/object.md) **property** The name of the property whose description is to be retrieved. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) A property descriptor of the given property if it exists on the object, undefined otherwise. **Sample** ```js const object1 = { property1: 42 }; const descriptor1 = Object.getOwnPropertyDescriptor(object1, 'property1'); application.output(descriptor1.configurable); // expected output: true application.output(descriptor1.value); //expected result is 42 ``` ### getOwnPropertyNames(object) Returns an array of all properties (including non-enumerable properties) found directly upon a given object. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object whose enumerable and non-enumerable own properties are to be returned. **Returns:** [Array](/reference/servoycore/dev-api/js-lib/array.md) An array of strings that correspond to the properties found directly upon the given object. **Sample** ```js const object1 = { a: 1, b: 2, c: 3}; application.output(Object.getOwnPropertyNames(object1)); ``` ### getPrototypeOf(object) Returns the prototype of the specified object. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object whose prototype is to be returned. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) The prototype of the given object. If there are no inherited properties, null is returned. **Sample** ```js const prototype1 = {}; const object1 = Object.create(prototype1); application.output(Object.getPrototypeOf(object1) === prototype1); // expected output: true ``` ### hasOwnProperty(prop) Determine whether the object has the specified property as its own property (as opposed to inheriting it). **Parameters** * [String](/reference/servoycore/dev-api/js-lib/string.md) **prop** The name of the property to test. **Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) A Boolean indicating whether or not the object has the specified property as own property. **Sample** ```js const object1 = new Object(); object1.property1 = 42; application.output(object1.hasOwnProperty('property1')); // expected output: true application.output(object1.hasOwnProperty('toString')); // expected output: false application.output(object1.hasOwnProperty('hasOwnProperty')); // expected output: false ``` ### is(value1, value2) Determines whether two values are the same value. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **value1** The first value to compare. * [Object](/reference/servoycore/dev-api/js-lib/object.md) **value2** The second value to compare. **Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) a Boolean indicating whether or not the two arguments are the same value. **Sample** ```js Object.is('foo', 'foo'); ``` ### isExtensible(object) Determines if an object is extensible (whether it can have new properties added to it).\ Objects are extensible by default, can be marked as non-extensible using Object.preventExtensions(), Object.seal(), or Object.freeze(). **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object which should be checked. **Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) A Boolean indicating whether or not the given object is extensible. **Sample** ```js var empty = {}; Object.isExtensible(empty); // === true Object.preventExtensions(empty); Object.isExtensible(empty); // === false var sealed = Object.seal({}); Object.isExtensible(sealed); // === false var frozen = Object.freeze({}); Object.isExtensible(frozen); // === false ``` ### isFrozen(object) Determines if an object is frozen. An object is frozen if and only if it is not extensible, all its properties are non-configurable, and all its data properties (that is, properties which are not accessor properties with getter or setter components) are non-writable. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object which should be checked. **Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) A Boolean indicating whether or not the given object is frozen. **Sample** ```js const object1 = { property1: 42 }; application.output(Object.isFrozen(object1)); // expected output: false Object.freeze(object1); application.output(Object.isFrozen(object1)); // expected output: true ``` ### isPrototypeOf(object) Checks if an object exists in another object's prototype chain. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object whose prototype chain will be searched. **Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) A Boolean indicating whether the calling object lies in the prototype chain of the specified object. **Sample** ```js function object1() {} function object2() {} object1.prototype = Object.create(object2.prototype); const object3 = new object1(); application.output(object1.prototype.isPrototypeOf(object3)); // expected output: true application.output(object2.prototype.isPrototypeOf(object3)); // expected output: true ``` ### isSealed(object) Determines if an object is sealed. An object is sealed if it is not extensible and if all its properties are non-configurable and therefore not removable (but not necessarily non-writable). **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object which should be checked. **Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) A Boolean indicating whether or not the given object is sealed. **Sample** ```js const object1 = { property1: 42 }; application.output(Object.isSealed(object1)); // expected output: false Object.seal(object1); application.output(Object.isSealed(object1)); // expected output: true ``` ### keys(object) Returns an array of all own enumerable properties found upon a given object, in the same order as that provided by a for-in loop (the difference being that a for-in loop enumerates properties in the prototype chain as well). **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** An array of strings that represent all the enumerable properties of the given object. **Returns:** [Array](/reference/servoycore/dev-api/js-lib/array.md) The object of which the enumerable's own properties are to be returned. **Sample** ```js const object1 = {a: 'somestring', b: 42, c: false }; application.outout(Object.keys(object1)); // expected output: Array ["a", "b", "c"] ``` ### preventExtensions(object) Prevents new properties from ever being added to an object (i.e. prevents future extensions to the object). **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object which should be made non-extensible. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) The object being made non-extensible. **Sample** ```js const object1 = {}; Object.preventExtensions(object1); try { Object.defineProperty(object1, 'property1', { value: 42 }); } catch (e) { application.output(e); } ``` ### propertyIsEnumerable(prop) Indicates whether the specified property is enumerable. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **prop** The name or symbol of the property to test. **Returns:** [Boolean](/reference/servoycore/dev-api/js-lib/boolean.md) A Boolean indicating whether the specified property is enumerable. **Sample** ```js const array1 = []; object1.property1 = 42; array1[0] = 42; application.output(object1.propertyIsEnumerable('property1')); // expected output: true application.output(array1.propertyIsEnumerable(0)); // expected output: true application.output(array1.propertyIsEnumerable('length')); // expected output: false ``` ### seal(object) Seals an object, preventing new properties from being added to it and marking all existing properties as non-configurable.\ Values of present properties can still be changed as long as they are writable. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object** The object which should be sealed. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) The object being sealed. **Sample** ```js const object1 = { property1: 42 }; Object.seal(object1); object1.property1 = 33; application.output(object1.property1); // expected output: 33 delete object1.property1; // cannot delete when sealed application.output(object1.property1); // expected output: 33 ``` ### setPrototypeOf(obj, prototype) Sets the prototype of a specified object to another object or null. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **obj** The object which is to have its prototype set. * [Object](/reference/servoycore/dev-api/js-lib/object.md) **prototype** The object's new prototype (an object or null). **Returns:** void **Sample** ```js const obj = {}; const parent = { foo: 'bar' }; application.output(obj.foo); // Expected output: undefined Object.setPrototypeOf(obj, parent); application.output(obj.foo); // Expected output: "bar" ``` ### toLocaleString() Returns a string representing the object. This method is meant to be overriden by derived objects for locale-specific purposes. **Returns:** [String](/reference/servoycore/dev-api/js-lib/string.md) A string representing the object. **Sample** ```js const number1 = 123456.789; application.output(number1.toLocaleString()); // expected output: "123.456,789" ``` ### toString() Returns a string representing the specified object. **Returns:** [String](/reference/servoycore/dev-api/js-lib/string.md) A string representing the object. **Sample** ```js function Dog(name) { this.name = name; } var dog1 = new Dog('Spike'); Dog.prototype.toString = function dogToString() { return this.name; } application.output(dog1.toString()); ``` ### valueOf() Returns the primitive value of the specified object. By default, the valueOf method is inherited by every object descended from Object.\ Every built-in core object overrides this method to return an appropriate value.\ If an object has no primitive value, valueOf returns the object itself. **Returns:** [Object](/reference/servoycore/dev-api/js-lib/object.md) The primitive value of the specified object. **Sample** ```js function MyNumberType(n) { this.number = n; } MyNumberType.prototype.valueOf = function() { return this.number; }; const object1 = new MyNumberType(4); application.output(object1 + 3); // expected output: 7 ``` ### values(object1) Returns an array whose elements are strings corresponding to the enumerable string-keyed property values found directly upon object. **Parameters** * [Object](/reference/servoycore/dev-api/js-lib/object.md) **object1** An object. **Returns:** [Array](/reference/servoycore/dev-api/js-lib/array.md) an array of a given object's own enumerable string-keyed property values. **Sample** ```js const object1 = { a: 'somestring', b: 42, c: false}; Object.values(object1); ``` *** --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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