How to Correctly Iterate Through HTMLCollection Elements and Retrieve Their IDs?

For Loop for HTMLCollection Elements

Explanation

You're attempting to iterate through an HTMLCollection and retrieve the ID of each element. However, your initial approach is incorrect. By using for (key in list), you're iterating over the keys of the HTMLCollection, which are the indices of the elements.

Correct Approach

To iterate over the HTMLCollection objects themselves and access their IDs, you can use the following yöntemler:

1. for/of Loop (Modern Browsers)

For modern browsers that support the ES6 for/of syntax, you can use the following code:

var list = document.getElementsByClassName("events");
for (let item of list) {
    console.log(item.id);
}

2. for Loop with Length Property

For browsers that do not support the for/of syntax, you can use the following code:

var list = document.getElementsByClassName("events");
for (var i = 0; i < list.length; i++) {
    console.log(list[i].id);
}

Avoid Using for/in

Do not use for/in to iterate over HTMLCollections. It's meant for iterating over object properties, which can lead to unexpected behavior with HTMLCollection objects.

Summary

Remember that for modern browsers, the recommended approach is to use the for/of syntax, while for older browsers, the for loop with length property approach will work. Avoid using for/in for HTMLCollections.

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