using System.Collections.Generic; namespace Common.Extensions { public static class StringToolsExtensions { /// <summary> /// Add a string to a list only if it doesnt already exist /// </summary> public static void AddUnique(this IList<string> self, string item) { if (!self.Contains(item)) self.Add(item); } public static void AddUniqueRange(this IList<string> self, IList<string> itemsToAdd) { foreach (var item in itemsToAdd) { if (!self.Contains(item)) self.Add(item); } } } }