Here you will learn objects, object literals, Object() constructor function, and access object in JavaScript. Show
You learned about primitive and structured data types in JavaScript. An object is a non-primitive, structured data type in JavaScript. Objects are same as variables in JavaScript, the only difference is that an object holds multiple values in terms of properties and methods. In JavaScript, an object can be created in two ways: 1) using Object Literal/Initializer Syntax 2) using the The following example demonstrates creating objects using both ways.
Above, Create Object using Object Literal Syntax The object literal is a short form of creating an object. Define an object in the var <object-name> = { key1: value1, key2: value2,...};
The following example demonstrates objects created using object literal syntax.
Note that the whole key-value pair must be declared. Declaring only a key without a value is invalid, as shown below.
Create Objects using Objects() Constructor Another way of creating objects is using the
An object can have variables as properties or can have computed properties, as shown below.
Access JavaScript Object Properties & Methods An object's properties can be accessed using the dot notation
In the above example, the Accessing undeclared properties of an object will return
undefined. If you are not sure whether an object has a particular property or not, then use the
The properties and methods will be available only to an object where they are declared.
Enumerate Object's Properties Use the
Pass by ReferenceObject in JavaScript passes by reference from one function to another.
Nested ObjectsAn object can be a property of another object. It is called a nested object.
How properties are assign to an object in JavaScript?JavaScript is designed on a simple object-based paradigm. An object is a collection of properties, and a property is an association between a name (or key) and a value. A property's value can be a function, in which case the property is known as a method.
How do you assign object properties?Object.assign() The Object.assign() method copies all enumerable own properties from one or more source objects to a target object. It returns the modified target object.
What are the properties of an object JavaScript?Object properties are defined as a simple association between name and value. All properties have a name and value is one of the attributes linked with the property, which defines the access granted to the property. Properties refer to the collection of values which are associated with the JavaScript object.
Can you add a property to an object in JavaScript?The name: values pairs in JavaScript objects are called properties. We can add the property to JavaScript object using a variable as the name by using dot notation or bracket notation.
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