How to Safely Remove Items from a Generic List During Iteration?

Avoiding Errors When Removing Items from a List During Iteration:

Modifying a list while iterating through it often leads to the "Collection was modified; enumeration operation may not execute" error. This happens because removing an item invalidates the iterator. Here's how to safely remove elements:

Method 1: Reverse Iteration

Iterating backward prevents index issues when removing items. This approach works well for simple removal criteria.

for (int i = safePendingList.Count - 1; i >= 0; i--)
{
    // Check removal condition
    if (shouldRemove)
    {
        safePendingList.RemoveAt(i);
    }
}

Method 2: RemoveAll Method

For more complex removal logic, the RemoveAll method provides a cleaner solution. It takes a predicate (a function that returns true if an item should be removed) and efficiently removes all matching elements.

safePendingList.RemoveAll(item => item.Value == someValue);

Summary:

These methods allow for safe and efficient removal of elements from a list during iteration, eliminating the risk of runtime exceptions. Choose the method best suited to your removal criteria and coding style.

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