In JavaScript, objects serve to hold data in key-value combinations. They facilitate the arrangement of information. This article will explore what JavaScript objects are, how to construct and utilize them, and some helpful functions that will assist you in managing objects.

Table of Contents:

• What is an Object in JavaScript?
• Creating JavaScript Objects
• Accessing Object Properties
• Modifying Object Properties
• Deleting Object Properties
• Methods in JavaScript Objects
• Common Mistakes with JavaScript Objects
• Conclusion
• JavaScript Objects – FAQs

What is an Object in JavaScript?

An object in JavaScript represents a set of data organized into key-value pairs. Keys may also be referred to as properties, each associated with a value. The values can encompass various types, including numbers, strings, or even other objects. Objects are instrumental in structuring related information.

Creating JavaScript Objects

There are two common methods for creating objects in JavaScript: using Object Literals and utilizing the new Object() syntax.

1. Using Object Literals

This is the most prevalent and straightforward approach to creating an object. An object is defined by enclosing key-value pairs within curly braces {}.

Example:

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function decodeHTML74250(input) { var doc = new DOMParser().parseFromString(input, “text/html”); return doc.documentElement.textContent; }

function copyCodeToClipboard74250() { const code = editor74250.getValue(); navigator.clipboard.writeText(code).then(() => { jQuery(“.maineditor74250 .copymessage”).show(); setTimeout(function() { jQuery(“.maineditor74250 .copymessage”).hide(); }, 2000); }).catch(err => { console.error(“Error copying code: “, err); }); }

function runCode74250() { var code = editor74250.getSession().getValue();

jQuery(“#runBtn74250 i.run-code”).show(); jQuery(“.output-tab”).click();

jQuery.ajax({ url: “https://intellipaat.com/blog/wp-admin/admin-ajax.php”, type: “post”, data: { language: “js”, code: code, cmd_line_args: “”, variablenames: “”, action:”compilerajax” }, success: function(response) { var myArray = response.split(“~”); var data = myArray[1];

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"+data+"

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function closeoutput74250() { var code = editor74250.getSession().getValue(); jQuery(“.maineditor74250 .code-editor-output”).hide(); }

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Output:

In this example,

• person is an object featuring three properties: name, age, and city, with each property assigned a respective value.

2. Using the new Object() Syntax

Additionally, you can generate an object using the new Object() constructor. While this method is not as common as the aforementioned one, it remains a valid approach.

Example:

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editor29055.setOptions({ maxLines: Infinity });

function decodeHTML29055(input) { var doc = new DOMParser().parseFromString(input, “text/html”); return doc.documentElement.textContent; }

// Function to copy code to clipboard function copyCodeToClipboard29055() { const code = editor29055.getValue(); // Retrieve code from the editor navigator.clipboard.writeText(code).then(() => { // alert(“Code copied to clipboard!”);

jQuery(“.maineditor29055 .copymessage”).show(); setTimeout(function() { jQuery(“.maineditor29055 .copymessage”).hide(); }, 2000); }).catch(err => { console.error(“Error copying code: “, err); }); }

function executeCode29055() {

var code = editor29055.getSession().getValue();

jQuery(“#runBtn29055 i.run-code”).show(); jQuery(“.output-tab”).click();

jQuery.ajax({ url: “https://intellipaat.com/blog/wp-admin/admin-ajax.php”, type: “post”,

data: { language: “js”, code: code, cmd_line_args: “”, variablenames: “”, action:”compilerajax” }, success: function(response) { var myArray = response.split(“~”); var data = myArray[1];

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Result:







In this example,

• A vacant object is generated using new Object().
• Subsequently, attributes are assigned to the object via dot notation.

Accessing Object Attributes

There are two methods to access the attributes of an object in JavaScript: Dot Notation and Bracket Notation.

1. Dot Notation

Dot notation stands out as the most common and straightforward method to access an object’s attributes. In this technique, you utilize the object’s name followed by a dot (.) and then the attribute name.

Illustration:

Output:

2. Bracket Notation

With Bracket notation, you can access properties of an object using square brackets ([]) alongside a string that denotes the property name. This method is particularly handy when the property name is saved in a variable or contains special symbols.

Example:

Output:

Altering Object Properties

In JavaScript, you have the capability to alter the properties of an object utilizing either dot notation or bracket notation.

1. Utilizing Dot Notation

You have the ability to directly modify the value of an existing property using dot notation by assigning a new value.

Example:

Output:

In this context,

• We revised the age attribute to 18 and updated the city attribute to Delhi.

2. Utilizing Bracket Notation

Bracket notation can likewise be employed to adjust object attributes, particularly when the attribute name is variable or encompasses special symbols.

Example:

Output:

Adjusting Non-Existent Properties

If you attempt to adjust a property that isn’t present, JavaScript will create it as a new property.

Example:

Result:

In this case,

• the city attribute didn’t exist initially, but it was added to the object when we assigned a value to it.

Removing Object Attributes

In JavaScript, you have the ability to delete attributes from an object using the delete operator. This operator erases the specified attribute from the object, leading to the absence of that attribute.

Note: Just like altering attributes, you can utilize both dot notation and bracket notation to remove attributes.

Syntax:

delete object.property;

delete object["property"];

Example: Utilizing both dot notation and bracket notation for removing attributes.

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// Function to copy code to clipboard function copyCodeToClipboard36402() { const code = editor36402.getValue(); // Retrieve code from the editor navigator.clipboard.writeText(code).then(() => { jQuery(".maineditor36402 .copymessage").show(); setTimeout(function() { jQuery(".maineditor36402 .copymessage").hide(); }, 2000); }).catch(err => { console.error("Error copying code: ", err); }); }

function runCode36402() { var code = editor36402.getSession().getValue();

jQuery("#runBtn36402 i.run-code").show(); jQuery(".output-tab").click();

jQuery.ajax({ url: "https://intellipaat.com/blog/wp-admin/admin-ajax.php", type: "post",

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Outcome:



Important Notes:

• The delete operator solely eliminates the property from the object and does not disrupt the variable that contains the object itself.
• Removing a property does not influence other attributes of the object.

Functions Within JavaScript Objects

In JavaScript, functions are stored as properties of objects. These functions, referred to as methods, enable you to execute actions relevant to the object. A method is merely a function associated with an object, capable of accessing and modifying that object’s properties.

Creating Methods in JavaScript Objects

Methods can be defined within an object in two distinct approaches: using function expressions or using shorthand method syntax.

1. Using Function Expressions:

This is the conventional method for creating a method within an object, where a property is assigned a function as its value.

Illustration:

Outcome:

2. Utilizing Shorthand Method Syntax:

In contemporary JavaScript (ES6+), methods can be defined using shorthand notation, which is simply a more concise version of Function Expression.

Illustration:

Output:

‘this’ Keyword in Methods

In JavaScript, ‘this’ points to the object it is part of. It is utilized to access properties and functions of an object. In the previous examples, this indicates the person object, hence this.name can retrieve the name attribute of the object.

Common Object Methods

JavaScript objects come equipped with built-in methods that can aid in interacting with them. Some frequently employed object methods are:

1. Object.keys()

This method produces an array containing an object's property names (keys).

Example:

Result:

2. Object.values()

This function produces an array of the values associated with an object’s properties.

Sample:

Result:

3. Object.entries()

This function generates an array of an object's key-value pairs represented as arrays.

Sample:

Output:

Frequent Errors with JavaScript Objects

Below are some typical errors individuals encounter when handling JavaScript objects. Let’s explore how you can evade them.

1. Accessing Non-existent Properties

Attempting to access a property that is not present will result in JavaScript returning undefined.

Example:

Output:

Solution: Ensure the property you are looking for exists within the code.

2. Unintentionally Overwriting Objects

In JavaScript, objects are references. When you assign one object to another, both references point to the same object, meaning any changes to one will reflect on the other.

Example:

Output:

Solution: Make a duplicate of the object so alterations will not influence the original object.

let courseCopy = { ...course };

3. Neglecting Parentheses for Methods

When invoking an object's method, you might sometimes forget to add parentheses (), which can lead to difficulties.

Example:

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// Function to copy code to clipboard function copyCodeToClipboard27738() { const code = editor27738.getValue(); // Extract code from the editor navigator.clipboard.writeText(code).then(() => { // alert("Code copied to clipboard!"); jQuery(".maineditor27738 .copymessage").show(); setTimeout(function() { jQuery(".maineditor27738 .copymessage").hide(); }, 2000); }).catch(err => { console.error("Error during code copy: ", err); }); }

function runCode27738() { var code = editor27738.getSession().getValue();

jQuery("#runBtn27738 i.run-code").show(); jQuery(".output-tab").click();

jQuery.ajax({ url: "https://intellipaat.com/blog/wp-admin/admin-ajax.php", type: "post", data: { language: "js", code: code, cmd_line_args: "", variablenames: "", action:"compilerajax" }, success: function(response) { var myArray = response.split("~"); var data = myArray[1];

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"+data+"");
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function closeoutput27738() {	
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document.getElementById("runBtn27738").addEventListener("click", runCode27738);
document.getElementById("closeoutputBtn27738").addEventListener("click", closeoutput27738);


Solution: Always include parentheses when calling a method.

person.greet();

Conclusion
Throughout this article, we have explored what JavaScript objects are, how to create and utilize them, along with some helpful methods. An object in JavaScript is essentially a collection of information stored in key-value pairs. Each key, also referred to as a property, is linked to a value, and...
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The values may be of various types, such as integers, strings, or even other entities. They assist in structuring and handling information efficiently.

JavaScript Objects – FAQs



Q1. In what ways can I generate an Object in JavaScript?

There are two primary approaches to create objects:

                Utilizing object literals ({})

                Employing the new Object() constructor



Q2. How can I retrieve the properties of an Object?

You can obtain properties using dot notation (e.g., object.property) or bracket notation (e.g., object[“property”]).



Q3. Is it possible to remove a property from an Object?

Indeed, you can eliminate a property from an object by using the delete operator. After it is removed, attempting to access that property will yield undefined.



Q4. What does the ‘this’ keyword signify in Objects?

Within an object, this refers to the object in question. It is frequently utilized in methods to reference the properties of the object.



Q5. What does Object Destructuring mean?

Object destructuring enables you to extract values from an object and assign them to variables in a more straightforward and comprehensible manner.





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