是的。它将创建新的列表实例。

现在要创建新列表时。它将复制其中的所有项。如果它是valuetype，则复制实际值，如果它是引用类型，则复制该引用。它是O(n)。

  class Program
 {
     static async Task Main(string[] args)
     {
         //Value Type
         List<int> valueTypeitems = new List<int>();
         valueTypeitems.Add(1);
         valueTypeitems.Add(2);

         var newlist = valueTypeitems.ToList();
         valueTypeitems[0] = 3; // This will only reflect in first list.
         valueTypeitems.ForEach(cc => Console.WriteLine(cc));
         newlist.ForEach(cc => Console.WriteLine(cc));

         //Reference type
         List<Test> refItems = new List<Test>();
         refItems.Add(new Test() { Value = 1 });
         refItems.Add(new Test() { Value = 2 });

         var newrefList = refItems.ToList();
         refItems.ForEach(cc => Console.WriteLine(cc.Value));
         newrefList.ForEach(cc => Console.WriteLine(cc.Value));
         refItems[0].Value = 10; //This reflect in both list. As object is same but you change value.

         refItems.ForEach(cc => Console.WriteLine(cc.Value));
         newrefList.ForEach(cc => Console.WriteLine(cc.Value));

         //if you actually change ref in one list then it will not reflect
         refItems[0] = new Test() { Value = 30 };
         refItems.ForEach(cc => Console.WriteLine(cc.Value));
         newrefList.ForEach(cc => Console.WriteLine(cc.Value));
         Console.ReadLine();
     }

     public class Test
     {
         public int Value { get; set; }
     }
 }