爲什麼我在這裏得到「預期的獲取或設置訪問器」？

Question

在下面的註釋行，爲什麼我收到錯誤

get或set訪問預計

???

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

namespace SingleLinkedList 
{ 

    class Program 
    { 
     static void Main(string[] args) 
     { 
     } 
    } 

    public class SingleLinkedList<T> 
    { 
     private class Node 
     { 
      T Val; 
      Node Next; 
     } 

     private Node _root = null; 

     public T this[int index] 
     { 
      for(Node cur = _root; // error pointing to here 
       index > 0 && cur != null; 
       --index, cur = cur.Next); 

      if(cur == null) 
       throw new IndexOutOfRangeException(); 

      return cur.Val; 

     } 

    } 
} 

Answer 1

你需要指定一個getter：

public T this[int index] 
{ 
    get 
    { 
     for(Node cur = _root; 
      index > 0 && cur != null; 
      --index, cur = cur.Next); 

     if(cur == null) 
      throw new IndexOutOfRangeException(); 

     return cur.Val; 
    } 
}