How to Safely Remove Items from an Array While Iterating in JavaScript?

Iterating Through Arrays and Removing Items Without Breaking the Loop

When removing items from an array within a loop, you may encounter an issue where splice() renders subsequent elements inaccessible. This is because splice() reindexes the array, potentially skipping items.

Problem:

In the following example, decrementing "seconds" and then splicing the item based on its negative value causes an undefined error:

for (i = 0, len = Auction.auctions.length; i <p><strong>Solution:</strong></p><p>To resolve this issue, consider two approaches:</p><ol>
<li>
<p><strong>Decrement Index After Splice()</strong>: After removing an item with splice(), decrement "i" to adjust for the reindexing:</p>
<pre class="brush:php;toolbar:false">for (i = 0, len = Auction.auctions.length; i 

Iterate in Reverse: Start the loop with the last index and iterate in reverse:

var i = Auction.auctions.length
while (i--) {
    ...
    if (...) { 
        Auction.auctions.splice(i, 1);
    } 
}

This way, the reindexing affects only subsequent elements, allowing for a continuous loop.

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