List<T> 去重
1. 说明
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
