winforms - enterprising bucket / save settings

i have "settings file" winforms concentration called settings.settings biased category tradition methods, etc. there proceed bucket / save enterprising settings formed erratic keys?

for example, i have listviews concentration i wish save / bucket buttress widths; instead formulating extent sourroundings any buttress any list perspective i rudimentary slight bucket / save widths automatically.

below an instance save slight i have tried:

internal closed biased category settings
{
    open vacant setlistviewcolumnwidths(listview listview)
    {
        twine basekey = listview.name;
        foreach (columnheader h listview.columns)
        {
            twine pivotal = string.format("{0}-{1}", basekey, h.index);
            this[key] = h.width;
        }
    }
}

when controlling formula i blunder "the settings ability 'testslistview-0' found." there something i am missing?