delete checked items from checkedListBox c#

Question

I want to remove several checked items from checkedListBox but I can't.This is my example. I was trying it but i was imposiible to get.

            for (int i = 0; i < checkedListBox1.Items.Count; i++){
            if (checkedListBox1.GetItemChecked(i))
            {
                checkedListBox1.Items.Remove(checkedListBox1.CheckedItems[i]);
            }
        }

Answer 1

Let's say you have a CheckedListBox of 2 items, both checked. If you delete item 1 then item 2 becomes the new item 1 and hence will never be deleted.

This is what's going on in detail:

1. i is initialized to 0.
2. i is less than checkedListBox1.Items.Count (which is 2). Loop entered.
3. checkedListBox1.GetItemChecked(i) returns true.
4. checkedListBox1.Items.Remove(checkedListBox1.CheckedItems[i]) removes item at index 0.
5. i is incremented to 1.
6. End of loop.
7. i is not less than checkedListBox1.Items.Count (which is 1) and the loop exits.

hence item 2 will not be deleted.

Reverse the loop and it should work:

for (int i = checkedListBox1.Items.Count - 1; i >= 0; i--)
{
  if (checkedListBox1.GetItemChecked(i))
  {
    checkedListBox1.Items.Remove(checkedListBox1.Items[i]);
  }
}

Another way of doing this is as follows:

while (checkedListBox1.CheckedItems.Count > 0)
{
  checkedListBox1.Items.RemoveAt(checkedListBox.CheckedIndices[0]);
}

And another:

while (checkedListBox1.CheckedItems.Count > 0)
{
    checkedListBox1.Items.Remove(checkedListBox1.CheckedItems[0]);
}

Yet another:

foreach (var i in checkedListBox1.CheckedIndices)
{
    checkedListBox1.Items.RemoveAt(i);
}

Going on:

for(var i = 0; i < checkedListBox1.CheckedItems.Count; i++)
{
    ((IList) checkedListBox1.CheckedItems).Remove(checkedListBox1.CheckedItems[0]);
}