循环后，如何从列表中删除重复项？

public static void FilterLockedThreads(List<string> Links, List<string> LockedLinks)
        {
            string number; 
            string number1;
            for (int i = 0; i < Links.Count; i++)
            {
                number = Links[i].Substring(32, 6);
                for (int x = 0; x < LockedLinks.Count; x++)
                {
                    number1 = LockedLinks[x].Substring(61, 6);
                    if (Links[i].Contains(LockedLinks[x]))
                    {

                        if (number == number1)
                        {
                            string identical = number;
                        }

                    }
                }
            }
        }
public static void FilterLockedThreads(List<str