What is this in JavaScript | this in JavaScript | JavaScript this keyword | this keyword

There are four ways a function can be called in JavaScript, hence there are four possible values of 'this' inside a JavaScript function.

This video explains those 4 invocation patterns in detail and most simplified ways.

1. Calling a function as function is also known as Function Invocation Pattern, here the value of 'this' is a global object

2. Calling a function as a constructor or using a new is also known as Constructor Invocation Pattern, here the value of 'this' is a newly created object.

3. A function can be called a method using an object is also known as Method Invocation Pattern., here the value of 'this' is an object before the dot

4. You can also indirectly call a function using the apply and call methods, it is also known as Indirect Invocation Pattern, here the value of 'this' can be passed manually. You can pass an existing object as the first parameter of apply() or call() and that object becomes the value of 'this' in the called function.

You can remember these as four formulas to find the value of 'this'. Whenever you have a function examine how that function is called to find the value of 'this'

note: Arrow function does not have its own 'this' object.

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[PamelaAnneHolmes]

You're an excellent teacher! Thank you for this video.

[namangarg]

I learned 'this' a thousand times but understood it best this time

[nikhleshkoshta]

Thanks DJ Sir,
Very well Explained, the concept of calling pattern of function.

[sandeeppetkar]

Thanks a lot for sharing this video.
One of the best tutorial to understand the concept of 'this'

[brijsharma]

plz try making more videos on similar topics that are very imp to understand.

[SumuduSiriwardana]

Well explained in a very simple format!

[chaudharyhit]

thank you sir for sharing 'this'😊😊