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JavaScript

Paul Brown
Paul Brown
7,057 Points
Posted by Paul Brown
Paul Brown
7,057 Points

Fascinating. $(this) doesn't work as expected with arrow function.

I was going crazy trying to figure out what the problem was. When using arrow function, e.g.:

$(.work).on('sticky-start', () => {
  $(this).append('blahblahblah');
});

I tried logging THIS, and it shows as being Window in this case.

So in case anyone else runs into this, hopefully this'll help!

Osaro Igbinovia
.a{fill-rule:evenodd;}techdegree
Osaro Igbinovia
Full Stack JavaScript Techdegree Student 15,928 Points

Yes I noticed it when I was learning jQuery Basics yesterday. You need to use the conventional 'function' style when constructing the function.

1 Answer

Paul Brown
Paul Brown
7,057 Points
Paul Brown
Paul Brown
7,057 Points

Right, so in case this is somehow unclear, the way to correct this problem is change the arrow function into a normal anonymous function: 

$(.work).on('sticky-start', function () {
  $(this).append('blahblahblah');
});

Now $(this) works.

Alexander La Bianca
Alexander La Bianca
15,959 Points

This is because 'this' with arrow functions and lexical scoping. Here are 2 good resources of why you had that experience.

https://toddmotto.com/es6-arrow-functions-syntaxes-and-lexical-scoping/

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions/Arrow_functions