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c# - find if an integer exists in a list of integers

i have this code:

  List<T> apps = getApps();

        List<int> ids;

        List<SelectListItem> dropdown = apps.ConvertAll(c => new SelectListItem
        {
            Selected = ids.Contains(c.Id),
            Text = c.Name,
            Value = c.Id.ToString()
        }).ToList();


ids.Contains

seems to always return false even though the numbers do match

any ideas?

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by (71.8m points)

If you just need a true/false result

bool isInList = intList.IndexOf(intVariable) != -1;

if the intVariable does not exist in the List it will return -1


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