Type Assertions & Type Casting | Typescript Tutorial for Beginners

Learn Type Assertions & Type Casting in this Typescript tutorial for beginners. Learn more about type assertions and type casting and complete a Typescript student challenge in detailed TS tutorial.

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Type Assertions & Type Casting | Typescript Tutorial for Beginners

(00:00) Intro
(00:05) Welcome
(00:28) Type Assertions vs Type Casting
(01:18) What are Type Assertions?
(01:58) Starter Code
(03:44) Converting Types with Assertions
(04:53) Angle Bracket Syntax instead of "as"
(05:55) Narrowing Return Values with Assertions
(08:37) Caution: Assertions allow mistakes!
(10:07) Double Casting and the unknown type
(12:03) DOM Selection Types
(16:19) Non-Null Assertions
(17:43) Angle Brackets and the DOM
(18:14) Student Challenge
(21:27) Solution 1: Beginners
(24:13) Solution 2: Type Assertion

Corrections:

📚 Suggested Pre-requisites for this Typescript course:

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Was this Typescript Assertions and Type Casting tutorial helpful? If so, please share. Let me know your thoughts in the comments.

#typescript #assertions #casting

[re.liable]

"strive for progress over perfection" this has gotten into my head. So simple but has a great effect.

I'm only a few vids in but I'm already thankful. You're awesome.

[evant]

I rarely have to rewind because the explanations are clear and concise from the start. Thanks man, the way you teach really sticks!

[oscardd]

Dave! I am waiting for a react typescript course/tutorial, maybe with avanced topics or a next js specialization too. You are the best!

[nguyenanh-vtjv]

Is this really free???? Unbelievable!!!! You are godsend, thank you Dave

[mohammadrezaakhshabi]

one of the best web developer teacher i have ever seen💙

[kirillzlobin]

The best content on Typescript on youtube

[sandyGamer]

@Dave, my solution for above challenge
const date: number = new Date().getFullYear();
const numberasString = (date as unknown) as string;
const span = as HTMLSpanElement;
const text =
span.appendChild(text);

[davidho]

You’re truly a life saver! The best web dev content creator !!!

[jdk]

Amazing content ! I dont know if you're planning to do a paid version going deeper in typescript with react / node one day, but ill be you first buyer ! Is The Complete Web Developer of the same quality as your videos?

[teetanrobotics]

Waiting for Nextjs 13 course. Amazing content as always professor. Thank you for your efforts

[kirillzlobin]

alt + z => wraps code to the next line
shift + alt + downArrow => copy selected code

[polopol]

What a champ! Are you planning some Docker tutorials? Since, for me, it is really a tough concept to get a grasp on. Thank you for content of course!

[Grishopping]

Gracias MAESTRO sigo Saludos desde Venezuela. Att. Jose Grillo

[ScriptRaccoon]

Great tutorial, as always! Currently I need to watch them with subtitles (my ears don't work properly 🤨), I am glad that YouTube creates them automatically and I can watch your videos. 🙂

[madhavjha]

Remember to keep striving for progress over perfection, a little progress every day will go a very long way.

[flowerofash]

amazing tutorial, btw i guess you don't have to explicitly say the const thisYear is string since the toString() is already called

[codie]

I might be wrong here but i think u can use angle brackets with react typescript for example i used it to define type of useState

[biLLie_wiLLie]

thank you for teaching! Big thank from Russia

[mhdfirassbarakat]

Dave, I have a piece of advice
can you please provide a couple of challenges to test our understanding of what you do?
I think it will be a useful
great job and keep going

[joojoogamer]

Great series. One question about type assertion (4.:48). I'm confused about how let c = a as Three. Why won't Typescript complain if I purposely initiate let a: One = "goodbye", since type Three has a literal type of "hello" which is different from variable a's value of "goodbye"? Thanks in advance.