c# - 我如何通过 Linq 实现它？

Question

例如，我有一个类如下:

public class SampleItem
{
    public string QCD { get; set; }
    public string CCD { get; set; }
    public string ITYPE { get; set; }
}

然后，我有一个列表:

var lstTest = new List<SampleItem>() { 

    new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "A"} ,
    new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "A"} ,
    new SampleItem(){ QCD = "Q1" ,  CCD = "C3" , ITYPE = "A"} ,

    new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "B"} ,
    new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "B"} ,
};

我想得到 2 个像这样的组

第 1 组:

new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "A"} ,
new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "A"} ,
new SampleItem(){ QCD = "Q1" ,  CCD = "C3" , ITYPE = "A"} ,

第 2 组:

new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "B"} ,
new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "B"} ,

所以，我只需要

lstTest.GroupBy (p=>new {p.QCD ,p.ITYPE});

但是现在，如果我的列表的顺序像下面这样

var lstTest = new List<SampleItem>() { 

    new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "B"} ,
    new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "B"} ,

    new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "A"} ,
    new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "A"} ,
    new SampleItem(){ QCD = "Q1" ,  CCD = "C3" , ITYPE = "A"} ,

    new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "B"} ,
    new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "B"} ,
};

我怎样才能得到像这样的 3 个组

第 1 组:

new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "B"} ,
new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "B"} ,

第 2 组:

new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "A"} ,
new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "A"} ,
new SampleItem(){ QCD = "Q1" ,  CCD = "C3" , ITYPE = "A"} ,

第 3 组:

new SampleItem(){ QCD = "Q1" ,  CCD = "C1" , ITYPE = "B"} ,
new SampleItem(){ QCD = "Q1" ,  CCD = "C2" , ITYPE = "B"} ,

通过LINQ？

非常感谢您的任何建议。

Answer 1

使用 GroupAdjacent 运算符，例如 one listed on Eric White's blog ，你可以这样做:

var groupedItems = lstTest.GroupAdjacent(p => new { p.QCD, p.ITYPE });