How can I access "this" in Typescript in the same way as I do in Javascript?

user_6011193 0
Viewed 234

in js, i use following code

function m() {
  console.log(this)
}

m()

this return current context

but in ts, I use following code, this return undefine

function m() {
    // @ts-ignore
    console.log(this)
}

m()

I hope use this get current context in typescript, how to do?

typescript javascript
4 Answers

It's because of 'use strict' which used in your typescript by default.

if you try this in js returns the same undefined

'use strict';

function m() {
  console.log(this)
}

m()
user_44979200

The issue is that when you use TS you are running in strict mode and, in strict mode, this of a function is undefined.

Thus for a strict mode function, the specified this is not boxed into an object, and if unspecified, this will be undefined:

source

user_142262700

Like the other answers tell you, it's because of the use strict of typescript. To be able to have a this context, you can (but shouldn't) use the new keyword.

playground

function m() {
  // @ts-ignore
  console.log(this);
}

// @ts-ignore
new m();
user_31069200

You can Try Like this,

const that = this;

function m() {
  console.log(that);
}

m();
user_105611910
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