linq distinct扩展

public static IEnumerable<TSource> DistinctBy<TSource, TKey> (this IEnumerable<TSource> source, Func<TSource, TKey> keySelector)
{
    HashSet<TKey> seenKeys = new HashSet<TKey>();
    foreach (TSource element in source)
    {
        if (seenKeys.Add(keySelector(element)))
        {
            yield return element;
        }
    }
}

使用方法如下(针对ID,和Name进行Distinct)
var query = people.DistinctBy(p => new { p.Id, p.Name });

若仅仅针对ID进行distinct:
var query = people.DistinctBy(p => p.Id);
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原文链接:https://blog.csdn.net/c1113072394/article/details/75330966/

原文地址:https://www.cnblogs.com/zengpeng/p/15098211.html