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Michael Pashkov
22,024 PointsCan we use arrow functions?
Like
$(document).ready(() => {
$('button').click(() => {
$(this).addClass("selected");
});
}); //end ready
instead of
$(document).ready(function () {
$('button').click(function () {
$(this).addClass("selected");
});
}); //end ready
Michael Pashkov
22,024 Points:) Interesting question, Dave. Why couldn't we use arrow function?
1 Answer
Dave StSomeWhere
19,870 PointsTesting it out and checking the documentation is the best way to figure it out.
The key issue as stated in the MDN Arrow Function Doc
An arrow function does not have its own this; the this value of the enclosing lexical context is used i.e. Arrow functions follow the normal variable lookup rules. So while searching for this which is not present in current scope they end up finding this from its enclosing scope . Thus, in the following code, the this within the function that is passed to setInterval has the same value as this in the lexically enclosing function:
So, if you test it out (check out this test pen
And you see the following in the console (also the class will only be added in the regular function):
"regular this is [object HTMLButtonElement]"
"arrow this is [object Window]"
Dave StSomeWhere
19,870 PointsDave StSomeWhere
19,870 PointsWhat happened when you tried it out?