Question

I have a problem with a foreach statement in my project. So far I have the code:

    foreach(object i in listboxFiles.Items)
    {
        if (i == ".ftpquota")
        {
            listboxFiles.Items.Remove(i);
        }
        if (i == ".")
        {
            listboxFiles.Items.Remove(i);
        }
        if (i == "..")
        {
            listboxFiles.Items.Remove(i);
        }
    }

I have this in a 1 second timer. It gets the item name all right, but when it gets to the if statements it says that they do not match, but they do?

Answer 1

First thing, you are changing a collection while iterating over it. This cannot work, so your code is fundamentally broken.

There are several ways to fix this; the simplest in your case would be to copy the items collection, iterating over the copy and changing (= removing from) the original:

var items = new System.Collections.ArrayList(listboxFiles.Items);

foreach (var item in items) {
    if (item.Equals("."))
        listboxFiles.Items.remove(item);
    …
}

Secondly, you are comparing an object to a string, hence the == operator does reference equality checking rather than testing for string equality. Either use Equals or do an appropriate cast.