Question

我用两个抽象方法创建了一个类。

在一个方法中，我按照抽象方法List中的返回类型的要求在列表中返回我的泛型类型U

在我的第二个方法中，我只是按照抽象方法中的返回类型的要求返回U，但是我得到了一个类型错误错误CS0029：无法隐式转换类型LB.HexSphereBuild.HexTile' to HexTile＆＃39;

我不明白为什么这是隐式转换？特别是因为除了使用LB.HexSphereBuild的公共抽象类AStarFindPath之外，所有类型都在LB.HexSphereBuild命名空间之下。

请帮忙

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

using LB.Managers;
using LB.HexSphereBuild;


namespace LB.AStarPathFinding
{
    public abstract class AStarFindPath<T,U> : MonoBehaviour{

        public virtual void FindPath<T>(Vector3 startPos, Vector3 targetPos) {
        }

        // Method 1
        public abstract U NodeFromWorldPoint<T,U> (Vector3 worldPos);

        // Method 2
        public abstract List<U> GetNodeNeighbours<U> (U node);
    }

}

这是继承我的抽象类

的类

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

using LB.Managers;
using LB.AStarPathFinding;

namespace LB.HexSphereBuild
{

    [RequireComponent (typeof(PlanetBuildManager))]
    public class AStarHexSphere: AStarFindPath<Hexsphere,HexTile>
    {

        private HexSphere _hexSphereObj;


        void Awake ()
        {

            // Reference to HexSphere 
            _hexSphereObj = gameObject.GetComponent<PlanetBuildManager> ().hexSphereObj;
        }


        override public HexTile NodeFromWorldPoint<HexSphere,HexTile> (Vector3 worldPos )
        {

            int startNodeIndex = _hexSphereObj.GetHexIndexFromPoint (worldPos);
            int startNodeIndex = _hexSphereObj.GetHexIndexFromPoint (worldPos);
            HexTile startHex =  _hexSphereObj.Hexes[startNodeIndex];// error CS0029: Cannot implicitly convert type `LB.HexSphereBuild.HexTile' to `HexTile'
            return startHex;
        }

        override public List<HexTile> GetNodeNeighbours<HexTile> (HexTile node )
        {

            List<HexTile> neighbours = new List<HexTile>();
            List<int> hexNeighboursIndices = new List<int>();
            int hexIndex =0;
            _hexSphereObj.GetNeighbors (hexIndex, ref hexNeighboursIndices);

            return neighbours;
        }

        public void FindPath (Vector3 startPos, Vector3 targetPos)
        {
            // Get HexTile from start and end positions
            int startNodeIndex = _hexSphereObj.GetHexIndexFromPoint (startPos);
            HexTile startHex = _hexSphereObj.Hexes [startNodeIndex];
            int targetNodeIndex = _hexSphereObj.GetHexIndexFromPoint (targetPos);
            HexTile endHex = _hexSphereObj.Hexes [targetNodeIndex];

        }
    }

}

添加属性，问题就在这里

using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System;

namespace LB.HexSphereBuild
{
    [System.Serializable]
    public class HexSphere
    {
        private List<HexTile> _hexes = new List<HexTile> ();
        // Data for the hexes. Read only
        public List<HexTile> Hexes {                             
            get{ return _hexes; }
        }
        // ....... other stuff
    }
}

添加数据类

namespace LB.HexSphereBuild
{
    public class HexTile : IAStarPathFinding<HexTile>
    {
        // Code .....
    }
}

Answer 1

您已经定义了T和U，在您的方法中再次定义意味着所有方法中的T可能是不同的类型。这不是你想要的，删除方法上的泛型：

public abstract class AStarFindPath<T,U> : MonoBehaviour
{
    public virtual void FindPath(Vector3 startPos, Vector3 targetPos) 
    {
    }

    // Method 1
    public abstract U NodeFromWorldPoint(Vector3 worldPos);

    // Method 2
    public abstract List<U> GetNodeNeighbours(U node);
}

理解为什么列表正在修复抽象方法类型

1 个答案: