如何将2D arraylist复制到另一个

Question

请告诉我如何在不引用相同数组实例的情况下将二维数组列表复制到另一个数组列表？

void partial_entropy(List<List<String>> class_lables)//This 2D "class_lables" arraylist contains many elements
{
    List<List<String>> lables1 = new List<List<String>>();
    lables1 = class_lables; //copying old arraylist to new array list called "lables1"
    //if I copy using the above method, both refer to same array instance.

    //Therefore, I would like to use something like "CopyTo" method
    class_lables.CopyTo(lables1, 0);//This did not work

    for (int x = 0; x < lables1.Count; x++)//To print out the newly copyed 2D array
    {
            for (int y = 0; y < 1; y++)
            {
                    Console.Write(lables1[x][y]+" ");
                    Console.WriteLine(lables1[x][y+1]);
            }
    }
}

Answer 1

List<string> tempList=new List<string>();
foreach (List<String> lst in class_lables)
{
    foreach (string str in lst)
            tempList.Add(str);
    lables1.Add(tempList);
    tempList.Clear();
}