Avoid this React State Mistake | React Previous State Explained

In this tutorial, React Previous State is explained. I will also explain why using setState with count + 1 is NOT wrong... but updating previous state in React requires an understanding of how state and re-rendering work together.

Avoid this React State Mistake | React Previous State Explained

(00:00) Intro
(00:05) count + 1 is NOT wrong
(01:12) Know when to use the right tool
(01:28) The Golden Rule
(02:09) Previous State function example
(03:05) Why prefer the prevState function
(07:28) Previous state with arrays
(10:03) Previous state with objects
(12:06) Summary

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#react #previous #state

[carsugarmodels]

The key phrase that explained everything "React updates state in batches". One another fantastic explanation from Dave. Thanks again!

[tankashing]

wow, i'm all the way from Malaysia, watched this video and thought to myself "finally, something i always was confused about, explained to me easily". Thank you soso much :)

[GabrielMartinez-ezue]

exactly the lecture i needed. incredible! i saw the exact same docs in reacts website and still could not understand when to use the previous state.

[ahmad-murery]

Updating the state using previous value did tricked me for a moment as I wasn't aware of it,
it's hard to forget what was learned from a mistake (my life story 🤦‍♂️)
Thanks for the update Dave,

[funnyway]

Thank you Dave ! you helped me having a better understanding of states in React

[mostinho]

Done thanks
Always use the version of state setter that takes the previous value because just setting the state without taking previous value doesn’t behave properly

[caffeinated-pixels]

Nice explanation Dave, this is definitely one of those state pitfalls that tend to confuse beginners.

[stillsmart]

That helped clarify a few important notions. Thank you!

[annemieknieboer]

Thank you so much for this clear explanation, you are a hero! Needed previous state for adding items to an array and got it working immediately after watching your tutorial 👏🥳

[jamshidtashkent]

Good lesson. Thank you. I'm trying to understand the lessons from the first lesson. Sometimes it is hard to get it but the next lessons seem very easy.

[avidambassador]

Great video, helped clear misconceptions with state. Cheers.

[matinsasan]

Thanks for clarifying how state update works, Dave.

[ohmygoodness]

Thank you that was very detailed and helpful

[cuberos]

How the same, This simple awesome explanation .Gray You are Great !!

[oussemabouyahia]

perfect content, thank you a lot for sharing knowledges

[houseofcoding]

thank you soo much dave. Great Explanation!

[jackiefranken]

Dave you just saved my demo. God bless

[nos-]

nice explanation ... but i was looking for the answer to WHY .. WHY and HOW prev state does what it does and WHY the currvalue doesnt work

[umeshpalsingh]

Thank you so much, Know I understand how prevState works

[Bskater]

Hey, first I just saw your playlists and they look great. I plan to watch all the videos available, but I was wondering, after learning react what's the point of using vanilla JS in projects instead of react?