Question

我有想要这样排序的列表

public class Refund {
    public int RefundStatus { get; set; }
    public DateTime SumbitTime { get; set; }
}

首先按RefundStatus排序，然后：

如果RefundStatus == 1然后以SumbitTime递增，

如果RefundStatus != 1，然后SumbitTime降序。

我应该如何通过linq to sql？

更新：我跟随Michal Turczyn进行了更改。但是日志输出显示无法翻译

Microsoft.EntityFrameworkCore.Query：警告：LINQ表达式 'orderby [p] .RefundStatus asc，（[[p] .SumbitTime.Ticks * Convert（IIF（（[[p] .RefundStatus == 1），1，-1），Int64））asc， EF.Property（？[p] ?,“ Id”）asc'无法翻译，将被翻译为本地评估。 Microsoft.EntityFrameworkCore.Query：警告： LINQ表达式'orderby [p] .RefundStatus asc，（[p] .SumbitTime.Ticks * Convert（IIF（（[[p] .RefundStatus == 1），1，-1），Int64））asc， EF.Property（？[p] ?,“ Id”）asc'无法翻译，将被翻译为本地评估。

Answer 1

我会通过以下方式做到这一点：

List<Refund> refundList = new List<Refund>();
// populate your list
refundList = refundList
    // here you could also use:
    //.OrderBy(r => r.RefundStatus)
    // but I don't know if you want it this way
    .OrderBy(r => (r.RefundStatus == 1 ? 1 : -1))
    .ThenBy(r => r.SubmitTime.Ticks * (r.RefundStatus == 1 ? 1 : -1))
    .ToList();

这个想法是，当您将-1中的滴答数乘以DateTime时，它将以降序排列，而不必将您的收藏分为两部分。

Answer 2

如果我正确理解了您的问题，这应该可以满足您的需求。

var sorted = refundList.GroupBy(refund => refund.RefundStatus)
    .SelectMany(
        group => group.Key == 1 
        ? group.OrderBy(p => p.SumbitTime)
        : group.OrderByDescending(p => p.SumbitTime))
    .ToList();

Answer 3

您可以使用以下内容。

var sorted = list.GroupBy(refund => refund.RefundStatus)
                 .OrderBy(x=>x.Key)
                 .SelectMany(
                             group => group.Key == 1 ? 
                             group.OrderBy(p => p.SubmitTime)
                             : group.OrderByDescending(p => p.SubmitTime));

完整示例。

        var random = new Random();
        var list = Enumerable.Range(1, 10)
            .Select(x => 
                new Refund
                {
                    RefundStatus = random.Next(0,2),
                    SubmitTime = DateTime.Now.AddMinutes(x)
                });

其中退款定义为

public class Refund
{
    public int RefundStatus { get; set; }
    public DateTime SubmitTime { get; set; }
}

示例输出

**排序前

Refund = 0 - SubmitTime = 22-03-2019 14:22:16
Refund = 1 - SubmitTime = 22-03-2019 14:23:16
Refund = 0 - SubmitTime = 22-03-2019 14:24:16
Refund = 0 - SubmitTime = 22-03-2019 14:25:16
Refund = 0 - SubmitTime = 22-03-2019 14:26:16
Refund = 1 - SubmitTime = 22-03-2019 14:27:16
Refund = 0 - SubmitTime = 22-03-2019 14:28:16
Refund = 1 - SubmitTime = 22-03-2019 14:29:16
Refund = 0 - SubmitTime = 22-03-2019 14:30:16
Refund = 1 - SubmitTime = 22-03-2019 14:31:16

排序后

Refund = 0 - SubmitTime = 22-03-2019 14:31:16
Refund = 0 - SubmitTime = 22-03-2019 14:29:16
Refund = 0 - SubmitTime = 22-03-2019 14:28:16
Refund = 0 - SubmitTime = 22-03-2019 14:26:16
Refund = 0 - SubmitTime = 22-03-2019 14:23:16
Refund = 1 - SubmitTime = 22-03-2019 14:22:16
Refund = 1 - SubmitTime = 22-03-2019 14:24:16
Refund = 1 - SubmitTime = 22-03-2019 14:25:16
Refund = 1 - SubmitTime = 22-03-2019 14:27:16
Refund = 1 - SubmitTime = 22-03-2019 14:30:16

使用linq to sql

3 个答案: