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JavaScript

Suan Choi
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Suan Choi
Front End Web Development Techdegree Graduate 16,587 Points
Posted by Suan Choi
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Suan Choi
Front End Web Development Techdegree Graduate 16,587 Points

Is it necessary to use anonymous arrow functions in onClick method for incrementScore/decrementScore?

It seems like it's working fine without arrow function, just like

<div className="counter">
    <button className="counter-action decrement" onClick={decrementScore}> - </button>
    <span className="counter-score">{score}</span>
    <button className="counter-action increment" onClick={incrementScore}> + </button>
</div>

2 Answers

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

The value assigned to the "onClick" property is a callback function.   :wink:

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Functionally, it makes no difference if the callback function is a named function or an anonymous one. It's your choice.

Suan Choi
seal-mask
.a{fill-rule:evenodd;}techdegree seal-36
Suan Choi
Front End Web Development Techdegree Graduate 16,587 Points
Suan Choi
.a{fill-rule:evenodd;}techdegree seal-36
Suan Choi
Front End Web Development Techdegree Graduate 16,587 Points

So in the video, she called the increment/decrement function inside anonymous arrow function and passed it to the onClick handler, rather than passing the increment/decrement functions by itself, as I wrote above. From my understanding she’s passing a function to call another function. Is that necessary?

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

It's probably not necessary unless there's a reason to create a specific scope for the actual handler. I'm not familiar with this particular lesson, so it might also be a convention established in previous examples.