c# - 按字母顺序排列列表，但某些元素始终位于顶部

Question

class Employee   
{
    static void Main(string[] args)
    {
        List<favorite> f = new List<favorite>();

        f.Add(new favorite {id = 1, title ="MEN" });
        f.Add(new favorite { id = 2, title = "WOMEN" });
        f.Add(new favorite { id = 3, title = "BOYS" });
        f.Add(new favorite { id = 4, title = "GIRLS" });
        f.Add(new favorite { id = 5, title = "Ajay" });
        f.Add(new favorite { id = 6, title = "vijay" });
        f.Add(new favorite { id = 7, title = "Jitu" });
        f.Add(new favorite { id = 8, title = "Suresh" });
        f.Add(new favorite { id = 9, title = "Ramesh" });
        f.Add(new favorite { id = 10, title = "Akshay" })

        foreach (var item in f.OrderBy(e=>e.title).ThenBy(e=>e.title))
        {
            Console.WriteLine(item.title);
        }
        Console.ReadLine();
    }

    class favorite
    {
        public int id { get; set; }
        public string title { get; set; }
    }
}

上面的列表有 4 个默认收藏夹(MEN、WOWEN、BOYS、GIRLS)，我希望始终位于顶部，所有其他收藏夹按字母顺序排列。

例子:我希望输出像

MEN
WOMEN
BOYS
GIRLS
AJAY
AKSHAY
JITU
LIKE
and so on ...

我想使用 Entity Framework Lambda 表达式执行此查询。
我尝试使用 OrderBy 和 ThenBy 来做到这一点，但还没有找到合适的解决方案。

Answer 1

如果你不想改变 favorite 类，你可以在某处定义这样的函数，

private static int GetPrimaryOrder(string title)
    {
        switch (title)
        {
            case "MEN":
                return 1;
            case "WOMEN":
                return 2;
            case "BOYS":
                return 3;
            case "GIRLS":
                return 4;
            default:
                return 5;
        }
    }

并将其用于初始订购，例如，

foreach (var item in f.OrderBy(x => GetPrimaryOrder(x.title)).ThenBy(e => e.title))
{
     Console.WriteLine(item.title);
}