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JavaScript Objects | Complete Guide

Abhishek Pathak on May 13, 2024

JavaScript Objects Similar to other programming languages javascript objects is a collection of key-value pairs, where each key is a str...

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Jon Randy 🎖️ • May 13 • Edited

You've missed Object.fromEntries as a creation method.

...where each key is a string...

Keys can also be Symbols

Properties of JS object can be accessed using dot notation and bracket notation

True if the key is a string, but if the key is a Symbol, bracket notation must be used.

Consider Object.create() that we used above. It is an method that creates a new object

Also important to note is that you can create an object with no prototype (a null prototype) by passing null as the first (prototype) parameter. This is useful for saving memory, creating enums, or dealing with objects that potentially use names that clash with default object methods.

heyeasley 🍓🥭 • May 13 • Edited

Beautiful. It's important to say for novels in models javascript.

Abhishek Pathak • May 13

thank you @jonrandy for the feedback. Really appreciate; and will surely change and add the statements.

Bek Brace • May 14

I appreciate your great effort, well done.
However the post is full of errors, please review your code snippets and republish it - we need to be responsible about the quality of information we provide to the audience.
Cheers my friend

Abhishek Pathak • May 14

hey bek
thank you for the awesome feedback
yes, I'm also improving the article daily so this can become one stop for the js object reference in dev to.

Bek Brace • May 14

Awesome, my friend !

Yogesh Galav • May 13 • Edited

I think there's a mistake in code of Object.freeze

        const me = { name:"Abhishek", age:21 }
        Object.freeze(me); // Freezing the object
        me.name = "scorcism";
        me.age = 22;
        console.log(me) 
        // Expected output: { name:"Abhishek", age:21 }

Abhishek Pathak • May 13

Thank you Yogesh,
Updated

WangLiwen • May 13

That's weird...

FrontEndWebDeveloping • May 13

If you mean the cover image, I agree.

Abhishek Pathak • May 13

haha, I am experimenting😅

FrontEndWebDeveloping • May 13

Keep it up! There's nothing wrong with it. It's just... unusual. 😄

Abhishek Pathak • May 13

hey,
can you elobrate so I can fix and improve.

Matt Lewandowski • May 13

You had my like just from the cover image 😂. Great article as well

Abhishek Pathak • May 13

haha tried something new😄

Suraj Upadhyay • May 14

A very good and informative article.

Abhishek Pathak • May 14

Thank you suraj

Kiran Shrinivas Gudigar • May 13

A great consolidation of javascript object

Abhishek Pathak • May 13

thank you kiran

Eckehard • May 13 • Edited

You are very unprecise about the use of "new" in 2. Using the new Keyword! See this example:

function About(name, age, city) {
      this.name = name;
      this.age = age;
      this.city = city;
  }   

const me = About("Abhishek", 21, "Mumbai"); 

console.log(name, age) // => Abhishek 21

"new" creates an object containing an internal "this". If you omit "new", this is the global context, so your properties are created outside of your object.

Using or not using "new" will lead to very hard to track errors. If you use "new" only 1,8% of the time, 98,2% your code will not work as expected.

Abhishek Pathak • May 14

Thank you eckehard for you feedback.
Will update the post,
those percentages i have put are for the methods you will use for creating objects😀

Jon Randy 🎖️ • May 14

Using new to create an instance of an object is very common. It's pretty much the basis of how OOP works in JS.

Alex P • May 13

Why you didn't review the valueOf?
That allows you to create "smart" & "magic" numbers or something else

Example: