如何在字典中使用Function作为值？ （C＃）

Question

我想创建一个字典并以特定的方式填充它。

public struct Position
{
    public int X { get; set; }
    public int Y { get; set; }
    public char Orientation { get; set; }
}

public Dictionary<Position, Position> ChangePosition;

取向可以是'N'，'S'，'E'，'W'表示北，南，......

当第一个键是 X，Y，'N' ---＆gt;值应为 X，Y + 1，'N'

因此，字典可以根据当前移动的位置和方向来预测项目的下一个位置。

如何填写这本词典？ 或者还有其他更好的实施方法吗？

任何帮助都将不胜感激。

更新

我找到了这个解决方案，但是我想类似Action<>之类的东西可能会让它变得更好：

ChangePosition= new Dictionary<char, Func<Position, Position>>
{
    {'N', pos => new Position {X = pos.X, Y = pos.Y + 1, Orientation = pos.Orientation}},
    {'E', pos => new Position {X = pos.X+1, Y = pos.Y , Orientation = pos.Orientation}},
    {'W', pos => new Position {X = pos.X-1, Y = pos.Y, Orientation = pos.Orientation}},
    {'S', pos => new Position {X = pos.X, Y = pos.Y - 1, Orientation = pos.Orientation}},
};

Answer 1

我强烈建议将Position定位为对象和指南针方向字符（'N'，'E'，'W'，'S'）枚举。生成的界面更清晰，更直观。

using System;
using System.Collections.Generic;

namespace DictionaryOfFunctions_StackOverflow
{
    class Program
    {
        static void Main(string[] args)
        {
            Position start = new Position()
            {
                X = 0,
                Y = 0,
                Orientation = CompassDirection.North
            };
            start.Move(CompassDirection.North, 5);
            start.Print(); // X: 0 Y: 5 Orientation: North
            start.Move(CompassDirection.SouthWest, 5);
            start.Print(); // X: -5 Y: 0 Orientation: SouthWest
            start.Move(CompassDirection.East);
            start.Print(); // X: -5 Y: 0 Orientation: East
            start.Move(dX: 5, dY: 1, newDirection: CompassDirection.West);
            start.Print(); // X: 0 Y: 1 Orientation: West
            start.Move(dY: -1, newDirection: CompassDirection.North);
            start.Print(); // X: 0 Y: 0 Orientation: North
            Console.ReadKey();
        }
    }

    public enum CompassDirection
    {
        NorthWest,
        North,
        NorthEast,
        East,
        SouthEast,
        South,
        SouthWest,
        West
    }

    public class Position
    {
        public CompassDirection Orientation { get; set; }
        public int X { get; set; }
        public int Y { get; set; }

        public void Move(int dX = 0, int dY = 0, CompassDirection? newDirection = null)
        {
            X += dX;
            Y += dY;
            Orientation = newDirection.HasValue ? newDirection.Value : Orientation;
        }

        public void Move(CompassDirection newDirection, int distance = 0)
        {
            var movement = new Dictionary<CompassDirection, Action>
            {
                {CompassDirection.NorthWest, () => Move(dY: 1, dX: -1)},
                {CompassDirection.North, () => Move(dY: 1)},
                {CompassDirection.NorthEast, () => Move(dY: 1, dX: 1)},
                {CompassDirection.East, () => Move(dX: 1)},
                {CompassDirection.SouthEast, () => Move(dY: -1, dX: 1)},
                {CompassDirection.South, () => Move(dY: -1)},
                {CompassDirection.SouthWest, () => Move(dY: -1, dX: -1)},
                {CompassDirection.West, () => Move(dX: -1)}
            };
            Orientation = newDirection;
            for (int i=0; i< distance; i++)
            {
                Action changePosition = movement[Orientation];
                changePosition();
            }
        }
    }

    public static class ExtensionMethods
    {
        public static void Print(this Position pos)
        {
            string display = $"X: {pos.X} Y: {pos.Y} Orientation: {pos.Orientation}";
            Console.WriteLine(display);
        }
    }
}