删除类似的列表框项

Question

I have a listbox with similar items, example: file1.exe=11, file1.exe=9 file2.exe=1, file3.zip=7, file7.zip=00, file3.zip=101 ...etc. Now what I have to do is remove the similar items so i end up with: file1.exe=11, file3.zip=7, file3.zip=101 .. and so on. The numbers at the end are random, what matters is i don't get the same file name more than once. Here is my lame attempt (overkill and does not work).

    public void RemoveListboxDuplicates(ListBox ListBox)
    {
        List<String> filenames = new List<String>();
        List<String> unique = new List<String>(); 
        foreach (string itm in ListBox.Items)
        {
                string fname = itm.Substring(0, itm.LastIndexOf("="));
                filenames.Add(fname);
        }

        for (int i=0;i<filenames.Count;i++) 
        {
            if(!lstFiles.Items[i].ToString().Contains(filenames[i])) {
                unique.Add(lstFiles.Items[i].ToString());
            }
        }
        lstFiles.Items.Clear();

        foreach (string itm in unique)
        {
            lstFiles.Items.Add(itm);
        }
    }  

Answer 1

If the numbers after = do not matter, one way of doing it is this:

List<String> all = new List<String>();
foreach (string itm in ListBox.Items) {
    all.Add(itm);
}
var unique = all
    .GroupBy(s => s.Split('=')[0])
    .Select(g => g.First())
    .ToList();

The s.Split('=')[0] operation chops off the part after = , and uses the prefix as a grouping key. Select(g => g.First()) part grabs the first element of each group, and ToList() makes the results into a List<string> again.