List<T> 去重

1. 说明

• 参考文档

2. 方法类

public class CommonEqualityComparer<T, V> : IEqualityComparer<T>
    {
        private Func<T, V> keySelector;

        public CommonEqualityComparer(Func<T, V> keySelector)
        {
            this.keySelector = keySelector;
        }

        public bool Equals(T x, T y)
        {
            return EqualityComparer<V>.Default.Equals(keySelector(x), keySelector(y));
        }

        public int GetHashCode(T obj)
        {
            return EqualityComparer<V>.Default.GetHashCode(keySelector(obj));
        }
    }

    public static class DistinctExtensions
    {
        public static IEnumerable<T> Distinct<T, V>(this IEnumerable<T> source, Func<T, V> keySelector)
        {
            return source.Distinct(new CommonEqualityComparer<T, V>(keySelector));
        }
    }

3. 演示

• 调用

comBookList = comBookList.Distinct(x => x.SShId).ToList();

• 上面不行就这样

 DistinctExtensions.Distinct(historyList,x=>x.Id).ToList();

4. 目录结构

QQ截图20230207171321.png