Question

如果我有如下的二维数组，是否可以按最后一个元素对数组进行排序？（最后一个元素是指2,10,1,5）

string[,] original = new string[4, 3] { {"apple","price1", "2"}, {"orange","price2", "10"} , {"Pineapple","price5", "1"}, {"Kiwi","price3", "5"}};

Answer 1

这并没有直接回答这个问题，但更清晰的实现可能就像......

public class Fruit : IComparer<Fruit>, IComparable<Fruit>
    {
        public Fruit(string name, double price, int quantity)
        {
            Name = name;
            Price = price;
            Quantity = quantity;
        }

        protected int Quantity { get; set; }

        protected double Price { get; set; }

        protected string Name { get; set; }

        public int CompareTo(Fruit other)
        {
            if (Quantity < other.Quantity) return 1;
            if (Quantity > other.Quantity) return -1;
            return 0;
        }

        public override string ToString()
        {
            return string.Format("{0} {1} {2}", Name, Price, Quantity);
        }

        public int Compare(Fruit x, Fruit y)
        {
            if (x.Quantity > y.Quantity) return 1;
            if (x.Quantity < y.Quantity) return -1;
            return 0;
        }
    }

然后你可以使用这样的新类...

var fruits = new List<Fruit>
                {
                    new Fruit("Apple", 0.30, 2),
                    new Fruit("Orange", 0.50, 10),
                    new Fruit("Pineapple", 0.35, 1),
                    new Fruit("Kiwi", 0.33, 5)
                };


            Console.WriteLine("Before sort");
            foreach (var fruit in fruits)
            {
                Console.WriteLine(fruit.ToString());
            }

            fruits.Sort();
            Console.WriteLine("After sort");
            foreach (var fruit in fruits)
            {
                Console.WriteLine(fruit.ToString());
            }

            fruits.Reverse();
            Console.WriteLine("After reverse");
            foreach (var fruit in fruits)
            {
                Console.WriteLine(fruit.ToString());
            }

            Console.ReadLine();

输出：

enter image description here

Answer 2

你可以做这样的事情

  public static void Sort(string[,] original)
    {
        var data=new List<List<string>>();
        for (int i = 0; i < original.GetLength(0); i++)
        {
            var m=new List<string>();
            for (int j = 0; j < original.GetLength(1); j++)
            {
               m.Add(original[i,j]) ; 
            }
            data.Add(m);
        }

        var l = data.OrderBy(x => int.Parse(x[2])).ToList();
        for (int i = 0; i < original.GetLength(0); i++)
        {
            for (int j = 0; j < original.GetLength(1); j++)
            {
                original[i, j] = l[i][j];
            }
        }
    }

Answer 3

这是可能的，但正如评论中已经指出的那样，有更好的方法来设计数据结构。无论如何，如果你想坚持你的阵列，可能的（有许多方法进行排序）解决方案可能如下所示：

string[,] original = new string[4, 3] 
{ 
    {"apple","price1", "2"}, 
    {"orange","price2", "10"} , 
    {"Pineapple","price5", "1"}, 
    {"Kiwi","price3", "5"}
};
// extract the data
var indexAndOrder = new List<Tuple<string, string, int>>();
for (var i = 0; i < original[0,0].Length - 1; i++)
{
    var current = int.Parse(original[i, 2]);
    indexAndOrder.Add(new Tuple<string, string, int>(original[i,0], original[i,1], current));
}
// anonymous object to sort the indices
var sortedArray = indexAndOrder
                        .Select (ao => new { Name = ao.Item1, Price = ao.Item2, Index = ao.Item3})
                        .ToList()               
                        .OrderBy (ao => ao.Index)
                        //.OrderByDescending (ao => ao.Index)
                        .ToArray();
foreach (var item in sortedArray)
{
    Console.WriteLine(string.Format("{0} - {1} - {2}", item.Index, item.Name, item.Price));
}

输出结果为：

1 - Pineapple - price5
2 - apple - price1
5 - Kiwi - price3
10 - orange - price2

该算法总是可以在函数中提取并返回一个新的排序数组。

Answer 4

作为参考，也可以使用单个LINQ查询（但可能不是最有效）：

string[,] original = new string[4, 3] { { "apple", "price1", "2" }, { "orange", "price2", "10" }, { "Pineapple", "price5", "1" }, { "Kiwi", "price3", "5" } };
var l = original.Cast<string>()
                .Select((element, index) => new { element, index })
                .GroupBy(x => x.index / 3)
                .Select(x => new
                {
                    Id = x.ElementAt(0).element,
                    Name = x.ElementAt(1).element,
                    Value = int.Parse(x.ElementAt(2).element)
                })
                .OrderBy(x => x.Value)
                .Select(x => new string[] { x.Id, x.Name, x.Value.ToString() })
                .ToArray();

请参阅this question了解详情。

Answer 5

static int MCompare(string[] x, string[] y)
{
    return String.Compare(x[2], y[2]);
}


static void Main(string[] args)
{

    string[,] original = new string[4, 3] 
    { 
        {"apple","price1", "2"}, 
        {"orange","price2", "10"} , 
        {"Pineapple","price5", "1"}, 
        {"Kiwi","price3", "5"}
    };
    string[][] temp = new string[4][];
    for (int i = 0; i < 4; i++)
    {
        temp[i] = new string[3];
        for (int j = 0; j < 3; j++)
        {
            temp[i][j] = original[i, j];
        }              

    }
    Array.Sort<string[]>(temp, MCompare);

}

tmp是排序结果

在C＃中，按其最后一个元素对数组进行排序

5 个答案: