如何使用自定義比較器在C＃中按字母順序對元素進行排序

Question

我是C＃的新手。 我正在嘗試編寫一個自定義比較器，該比較器按城市名稱的字母順序對CityInfo對象的列表進行排序。

 public class CityInfoComparer 
    {
        private readonly IComparer<string> _baseComparer;

        public CityInfoComparer(IComparer<string> baseComparer) 
        {
            _baseComparer = baseComparer;
        }

        public int Compare(CityInfo city1, CityInfo city2)
        {
            return _baseComparer.Compare(city1.CityName, city2.CityName);

        }
    }


public class CityList
    {
        public List<CityInfo> CityInfos { get; set; }

        public void Sort(CityInfo city1, CityInfo city2)
        {
            CityInfos.Sort(new CityInfoComparer(StringComparer.CurrentCulture));

            //CityInfos.Sort()
        }

    }

我在此行出現錯誤：

CityInfos.Sort（new CityInfoComparer（StringComparer.CurrentCulture））;

無法從CityInfo轉換為Systems.Generic.Collections.Icomparer

Answer 1

您應該繼承自IComparer，請參見下文：

public class CityInfoComparer:IComparer<CityInfo>
{
    private readonly IComparer<string> _baseComparer;

    public CityInfoComparer(IComparer<string> baseComparer)
    {
        _baseComparer = baseComparer;
    }

    public int Compare(CityInfo city1, CityInfo city2)
    {
        return _baseComparer.Compare(city1.CityName, city2.CityName);
    }
}


public class CityList
{
    public List<CityInfo> CityInfos { get; set; }

    public void Sort()
    {
        CityInfos.Sort( new CityInfoComparer(StringComparer.CurrentCulture));
    }

}