Question

我有两个列表 - 访客列表和VIP列表。我需要对Guest列表进行排序，以便如果它包含VIP列表中的第一个人，则它们会转到列表的顶部，依此类推。在VIP列表用尽之后，访客列表的其余部分保持原始顺序。订购必须同时使用名字和姓氏。我使用List和foreach语句完成了这项工作，但似乎应该有更优雅的方式。

是否有更简单，更现代的方式进行此类排序？

class Guest 
{
    public int NumberInParty { get; set; }
    public string FirstName { get; set; }
    public string LastName { get; set; }
}

class VIP
{
    public string FirstName { get; set; }
    public string LastName { get; set; }
}

class TrackedGuest
{
    public Guest guest;
    public bool isTaken;

    public TrackedGuest(Guest g)
    {
        this.guest = g;
        isTaken = false;
    }
}

static void Main(string[] args)
{
    List<Guest> guests = new List<Guest>();

    guests.Add(new Guest { FirstName = "Rob", LastName = "Carson", NumberInParty = 5 });
    guests.Add(new Guest { FirstName = "George", LastName = "Waverly", NumberInParty = 3 });
    guests.Add(new Guest { FirstName = "Pete", LastName = "Spacely", NumberInParty = 2 });
    guests.Add(new Guest { FirstName = "George", LastName = "Jetson", NumberInParty = 6 });
    guests.Add(new Guest { FirstName = "Cosmo", LastName = "Spacely", NumberInParty = 2 });

    List<VIP> vips = new List<VIP>();
    vips.Add(new VIP { FirstName = "George", LastName = "Jetson" });
    vips.Add(new VIP { FirstName = "Cosmo", LastName = "Spacely" });

    List<TrackedGuest> TrackedGuests = new List<TrackedGuest>();

    foreach (Guest g in guests)
    {
        TrackedGuests.Add(new TrackedGuest(g));
    }

    List<Guest>SortedGuests = new List<Guest>();

    // Copy each guest on the VIP list in order
    foreach (VIP vip in vips)
    {
        foreach (TrackedGuest tGuest in TrackedGuests)
        {
            if (
                (tGuest.isTaken == false) &&
                (vip.FirstName == tGuest.guest.FirstName) &&
                (vip.LastName == tGuest.guest.LastName)
                )
            {
                SortedGuests.Add(tGuest.guest);
                tGuest.isTaken = true;
            }
        }        
    }

    // Process the rest of the guests
    if (SortedGuests.Count < guests.Count)
    {
        foreach (TrackedGuest tGuest in TrackedGuests)
        {
            if (tGuest.isTaken == false)
            {
                SortedGuests.Add(tGuest.guest);
                tGuest.isTaken = true;
            }
        }
    }

    foreach (Guest guest in SortedGuests)
    {
        Console.WriteLine(guest.FirstName + " " + guest.LastName + ": " + guest.NumberInParty + " in party.");

    }

    Console.ReadLine();
}

Answer 1

var sorted = new List<Guest>();
var guestvips = from g in guests
                from v in vips.Where(vip => vip.FirstName == g.FirstName && vip.LastName == g.LastName).DefaultIfEmpty()
                where v != null
                select g;
var guestsimple = from g in guests
                  from v in vips.Where(vip => vip.FirstName == g.FirstName && vip.LastName == g.LastName).DefaultIfEmpty()
                  where v == null
                  select g;

sorted.AddRange(guestvips.Concat(guestsimple));

此代码＆＃39;离开加入＆＃39;客人点了两次。在第一种情况下，它需要那些具有相同VIP的客户，其次是那些没有相同VIP的客户。第一种情况可以通过＆＃39; join＆＃39;重写。实际上是关键字。

Answer 2

// dictionary to easily get vips order
// uses anonymous types, to get value equality for free
var vipsOrder = vips.Select((v, i) => new { v, i })
                    .ToDictionary(x => new { x.v.FirstName, x.v.LastName },
                                  x => x.i);

// sort first by order taken from vipsOrder and then by name
var sortedGuests = (from g in guests
                    let info = new { g.FirstName, g.LastName }
                    let oorder
                     = vipsOrder.ContainsKey(info)
                         ? vipsOrder[info] : vips.Count
                    orderby oorder, info.FirstName, info.LastName
                    select g).ToList();

需要更好的方法将一个列表与另一个列表排序

2 个答案: