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Aakash Srivastav
Full Stack JavaScript Techdegree Student 11,626 PointsListening for Events with addEventListener()
What if I use for loop
within each event handler just like-
listItems.addEventListener('mouseover', () => {
for(let i = 0 ; i< listItems.length ; i+=1){
listItems[i].textContent = listItems[i].textContent.toUpperCase();
}
listItems.addEventListener('mouseout', () => {
for(let i = 0 ; i< listItems.length ; i+=1){
listItems[i].textContent = listItems[i].textContent.toLowerCase();
}
Is it correct?If not why?
1 Answer

Steven Parker
220,450 PointsThis code doesn't show how "listItems" is established, but since it is being indexed and used in a loop, I assume that it represents an HTMLcollection. But a collection would not have a "addEventListener" method, only the individual elements would have that.
Also, it looks like the closing brace and parenthesis are missing from each function.
Aakash Srivastav
Full Stack JavaScript Techdegree Student 11,626 PointsAakash Srivastav
Full Stack JavaScript Techdegree Student 11,626 PointsBut a collection would not have a "addEventListener" method, only the individual elements would have that.
I didn't know that . It clears all my doubt. Thanks Steven