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  • LINQ

    var racers = Formula1.GetChampions().
                    Where(r => r.Wins > 15 && (r.Country == "Brazil" || r.Country == "Austria")).
                    Select(r=>r);
                foreach (var item in racers)
                {
                    Console.WriteLine("{0:A}",item);
                }

    索引传递

    var racers = Formula1.GetChampions().Where((r, index) => r.LastName.StartsWith("A") && index % 2 != 0);
                foreach (var item in racers)
                {
                    Console.WriteLine("{0:A}", item);
                }

    linq分组、排序、选择特定值(其中Coun,C可以理解为结果的属性)

    var country = Formula1.GetChampions().GroupBy(r => r.Country).OrderByDescending(g => g.Count()).
    ThenBy(g => g.Key).Where(g => g.Count() > 2).Select(g => new { Coun = g.Key, C = g.Count() });

    分页分区

    int pageSize = 5;
    int pageNumber = (int)Math.Ceiling(Formula1.GetChampions().Count() / (double)pageSize);
    for (int page = 0; page < pageNumber; page++)
    {
    Console.WriteLine("page {0}",page);
    var racers = (from r in Formula1.GetChampions() orderby r.LastName select r.FirstName + " " + r.LastName).Skip(page * pageSize).Take(pageSize);
    foreach (var item in racers)
    {
    Console.WriteLine(item);
    }
    }

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  • 原文地址:https://www.cnblogs.com/yj2010/p/4122779.html
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