Question

理想情况下，我想添加到NumberList，而不删除它制作另一个NumberList，并将其添加到NumberRanges，List。

//How to add 8 to NumberRanges.NumberGroup.GroupEven
//How to add 9 to NumberRanges.NumberGroup.GroupOdd
AddEvenNumberToRange(oNumberRanges, 8);
AddOddNumberToRange(oNumberRanges, 9);


using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Collections;

namespace AddToList
{
    class Program
    {
        static void Main(string[] args)
        {
            NumberList oGroupEven = new NumberList();
            InitialLoadEvenNumbers(oGroupEven);
            NumberList oGroupOdd = new NumberList();
            InitialLoadOddNumbers(oGroupOdd);

            NumberRanges oNumberRanges = new NumberRanges();
            CombineNumberRanges(oGroupEven, oGroupOdd, oNumberRanges);
            OutPutRanges(oNumberRanges);
            Console.ReadKey();

            //This code below will throw execption unitl implemented.
            //How to add 8 to NumberRanges.NumberGroup.GroupEven
            //How to add 9 to NumberRanges.NumberGroup.GroupOdd
            AddEvenNumberToRange(oNumberRanges, 8);
            AddOddNumberToRange(oNumberRanges, 9);
            OutPutRanges(oNumberRanges);

            Console.ReadKey();
        }

        private static void AddOddNumberToRange(NumberRanges oNumberRanges, int p)
        { 
            //I'm stuck on the best approach to add a number to existing collection
            throw new NotImplementedException();
        }

        private static void AddEvenNumberToRange(NumberRanges oNumberRanges, int p)
        {
            //I'm stuck on the best approach to add a number to existing collection
            throw new NotImplementedException();
        }


        private static void OutPutRanges(NumberRanges oNumberRanges)
        {
            foreach (NumberList olist in oNumberRanges)
            {
                foreach (int iNum in olist)
                {
                    Console.WriteLine(iNum.ToString());
                }
            }
        }

        private static void CombineNumberRanges(NumberList oGroupEven, NumberList oGroupOdd, NumberRanges oNumberRanges)
        {
            oNumberRanges.NumberGroups.Add(oGroupEven);
            oNumberRanges.NumberGroups.Add(oGroupOdd);
        }

        private static void InitialLoadOddNumbers(NumberList oGroupOdd)
        {
            oGroupOdd.Number.Add(3);
            oGroupOdd.Number.Add(5);
            oGroupOdd.Number.Add(7);
        }

        private static void InitialLoadEvenNumbers(NumberList oGroupEven)
        {
            oGroupEven.Number.Add(2);
            oGroupEven.Number.Add(4);
            oGroupEven.Number.Add(6);
        }
    }

    public class NumberList : IEnumerator, IEnumerable
    {

       public List<int> Number = new List<int>();

       #region GetEnumeratorSetup
       private int m_iPosition = -1;

       public IEnumerator GetEnumerator()
       {
           return Number.GetEnumerator();
       }

       public object Current
       {
           get
           {
               return Number;
           }
       }

       public bool MoveNext()
       {
            m_iPosition++;
            return true;
       }

       public void Reset()
       {
           m_iPosition = 0;
       }
       #endregion
    }

    public class NumberRanges: IEnumerator, IEnumerable
    {
        public List<NumberList> NumberGroups = new List<NumberList>();

        #region EnumerationSetup
        private int m_iPosition = -1;
        public object Current
        {
            get
            {
                return NumberGroups;
            }
        }

        public bool MoveNext()
        {
            m_iPosition++;
            return true;
        }

        public void Reset()
        {
            m_iPosition = 0;
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return NumberGroups.GetEnumerator();
        }
        #endregion
    }
}

Answer 1

List<T>真的是要走的路（正如svick指出的那样），但是如果你必须这样做，那么在我看来下面的内容最简单：

private static void AddOddNumberToRange(NumberRanges oNumberRanges, int p)
{ 
    oNumberRanges.NumberGroups[1].Number.Add(p);
}

private static void AddEvenNumberToRange(NumberRanges oNumberRanges, int p)
{
    oNumberRanges.NumberGroups[0].Number.Add(p);
}

这将在第二次调用OutPutRanges时产生以下输出：

使用List<T>

如果您想使用List<T>，则需要两个List<int>（oGroupEven和oGroupOdd），以及一个List<List<int>>用于oNumberRanges。如果需要，您可以实际摆脱oGroupEven和oGroupOdd并使用一个List<List<int>>来获取上面的代码并将其压缩为Main方法中的几行代码：

    static void Main(string[] args)
    {
        // Create the oNumberRanges and initialize it with the even and odd lists
        List<List<int>> oNumberRanges = new List<List<int>>() { new List<int>(){ 2, 4, 6}, new List<int>() { 3, 5, 7 } };

        OutPutRanges(oNumberRanges);
        Console.ReadKey();

        // Add 8 to the even list
        oNumberRanges[0].Add(8);
        // Add 9 to the odd list
        oNumberRanges[1].Add(9);

        OutPutRanges(oNumberRanges);

        Console.ReadKey();
    }

    private static void OutPutRanges(List<List<int>> oNumberRanges)
    {
        foreach (List<int> olist in oNumberRanges)
        {
            foreach (int iNum in olist)
            {
                Console.WriteLine(iNum.ToString());
            }
        }
    }

哪会产生以下输出：

如何添加到列表集合一旦添加到另一个列表集合？

1 个答案: