JavaScript Callbacks & Promises | Sigma Web Development Course - Tutorial #75

Показать описание

➡️ English Subtitles are now up for all the videos!

python, C, C++, Java, JavaScript and Other Cheatsheets [++]:

►Learn in One Video[++]:

►Complete course [playlist]:

Follow Me On Social Media
Comment "#HarryBhai" if you read this 😉😉

CodeWithHarry

Рекомендации по теме

Комментарии

75 day challenge complete 😮😮❤❤
Perfectly explained Harry Bhai
#SigmaBatchOP

hiphop

What a coincidence
We just had a lecture on promises in morning and no one understood that.
But now can.
Thanks sir

harishbhise

if any one is facing issue in understanding callback & promise concept. checkout the Namaste JavaScript series by AKSHAY SAINI, it's a great series which covers some advance topic which are also important from the perspective of interview. Moreover it's the deep explanation of the topics.

sahilkhandekar

To people who can't understand it:
Don't panic. Use multiple resources, listen to all of them define promises and callbacks. Then get a notebook and write your general understanding of whatever you have learnt. Write the code in videos by yourself and if you can't understand any part of it use chat GPT. You will understand it in 2-3 days (not fully but have a grasp)

Akshat_Sinha_

00:01 Callbacks are functions used to call a function and can be passed as arguments.
02:14 JavaScript uses asynchronous functions to postpone execution.
06:00 Installing ES7 React Redux Extension
08:06 Using callback to load script and control function execution
11:50 JavaScript Promise is the solution to callback hell
13:50 Using Promises in JavaScript instead of waiting for callbacks
17:29 Understanding JavaScript Promises and their handling
19:19 Explaining JavaScript promises and handling resolve and reject scenarios
22:47 Handling network request responses with JavaScript Callbacks & Promises
24:19 Promise chaining allows passing resolved values through multiple handlers.
27:47 Understanding the difference between resolved and settled promises
29:23 Using promise.race to show the image of the promise resolved first among the five.

Billionaire-whfp

Took a months break and starting again today, felt like I need to revise previous topics to understand all the new concepts.
Also writing this comment to make a note to self that I must catch up again.
So, if you are watching this series in the future. I have a few things that'll help you stay consistent :-
- Revise, all the topics. It'll take a few minutes if you do it daily, but is a really important thing to do.

- It's alright if you have fallen behind, catching up again is important and should be priority.
So yea, keep watching and learning. You'll complete the series and gain good amount of knowledge about web dev.
#SigmaBatchOP

KoderKapil

from DOCTYPE to today I have written and implemented the code in VS code. with our writing, it's not easy to understandout
Thank sir
the course is outstanding

Yasinkhan-tmjv

This is a great series. Every concept is being cleared in a simplified manner.👍👍

ombhandwaldar

This is the most important part and problematic part for me since I've started using pure js for my projects. The video works like "cherries on a cake". Thanks Harry bhai for furnishing us with great concepts.❤

lakshyarajdash

Thank you Harry Bhai for your sincere efforts, I promise I will do my best from my side and I've already commented my feedback on the first video of this Sigma course

iam_aryann

first 13mins mere to out of head gyi h. fir se dekhni pdegi

chahatkumar

Very easy to understand, such a great teacher 😊

thoropyt

🎯 Key Takeaways for quick navigation:

00:00 📚 *Introduction to Callback Functions and Promises*
- Callback functions are functions passed into another function as an argument, invoked inside the outer function to complete an action.
- Asynchronous nature of JavaScript explained with examples of setTimeout and console.log order of execution.
- Callback functions allow for asynchronous programming but can lead to callback hell or pyramid of doom.
04:06 🔄 *Managing Callback Hell with Promises*
- Promises provide a solution to callback hell, offering a cleaner and more manageable way to handle asynchronous code.
- Promises represent a guarantee of code execution, useful for waiting on tasks without blocking other operations.
- Creating and utilizing promises allows for more organized and structured code, improving readability and maintainability.
17:21 🔒 *Promises and Resolve/Reject Mechanism*
- Understanding the concept of promises and their role in code execution.
- Explanation of the resolve and reject functions within a promise.
- Demonstrating how to use `resolve` to indicate successful completion of a task and `reject` to handle errors.
19:34 🛠️ *Handling Promise Results and Errors*
- Using `.then` to access the resolved value of a promise and perform further actions.
- Implementing `.catch` to handle errors that occur during promise execution.
- Emphasizing the importance of error handling in asynchronous code execution.
24:15 🔄 *Promise Chaining and Promise.finally*
- Understanding promise chaining to pass resolved values between promises.
- Introduction to `promise.finally` for performing cleanup actions after promise execution.
- Explaining the concept of passing resolved values through a chain of `.then` handlers.
26:06 🤝 *Promise.all and Promise.race*
- Utilizing `Promise.all` to wait for multiple promises to resolve and gather their results.
- Introduction to `Promise.race` for determining the fastest resolving promise among multiple promises.
- Illustrating scenarios where `Promise.all` and `Promise.race` are beneficial, such as handling multiple network requests or downloads.
28:54 ⚖️ *Understanding Promise.all settled and
- Explaining `Promise.all settled` to handle both resolved and rejected promises.
- Introducing `Promise.resolve` and `Promise.reject` to create promises with predefined states.
- Demonstrating how to handle promises with different states and reasons using these methods.

Made with HARPA AI

Hafijur