Question

I have a ListView to show some images (using ImageList). Everything works fine so far. I can sort items by theire Text property easily. But I want to be able to sort them by theire creation date as well (ASC or DESC).

Items are created like this:

Item.Text = file name
item.Tag = file path

I am trying to sort the date like this but no success in sorting the dictionary, and also I have no idea how to cast that dictionary items back into listview:

private void menuViewSortDate_Click(object sender, EventArgs e)
{
    var files = new Dictionary<ListViewItem, DateTime>();

    foreach(ListViewItem item in listViewLoadedImages.Items)
    {
        files.Add(item, File.GetCreationTime(item.Tag.ToString()));
    }

    listViewLoadedImages.BeginUpdate();
    listViewLoadedImages.Items.Clear();

    // how to sort dictionary by DateTime ??
    // like files.Sort(bydate);

    //How can refer to key values (listviewitems) in dictionary
    listViewLoadedImages.Items.AddRange((ListViewItem)files.Keys); 

    listViewLoadedImages.EndUpdate();
} 

Answer 1

As Avner says a dictionary is not ordered by default however you could use some LINQ to return a IEnumerable by doing:

var results = files.OrderBy(x=>x.Value);

I’m also not sure how you can make a ListViewItem unique as your key however you could try and cast your dictionary keys

var lvItems = files.Keys.Cast<ListViewItem>();