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Khue Luu
5,148 PointsWhy we have to use the double equal sign in the if condition?
Hi everyone,
My code only runs when the equal size in the if condition () is doubled, and the equal size in the {} is single. Could you please explain?
Here's my code:
toggleList.addEventListener ( 'click', () => { if (divList.style.display == "none") { divList.style.display = "block"; toggleList.textContent = "Hide List"; } else { divList.style.display = "none"; toggleList.textContent = "Show List"; }
});
Thank you so much!
2 Answers
andren
28,558 Points== is an equality comparison operator, it is used to compare two values. So in your if statement you are asking JavaScript to see if divList.style.display is equal to "None".
= is an assignment operator, it tells JavaScript that you want to assign a value to something. So inside of your if/else code blocks you are assigning values to divList.style.display and toggleList.textContent.
So the short answer is that they do different things, and as such aren't interchangeable.
Khue Luu
5,148 PointsThank you so much Andren!