使用LINQ标准化数据

Question

假设我们有一些非规范化数据,如下所示:

List<string[]> dataSource = new List<string[]>();
string [] row1 = {"grandParentTitle1", "parentTitle1", "childTitle1"}; 
string [] row2 = {"grandParentTitle1", "parentTitle1", "childTitle2"};
string [] row3 = {"grandParentTitle1", "parentTitle2", "childTitle3"};
string [] row4 = {"grandParentTitle1", "parentTitle2", "childTitle4"};
dataSource.Add(row1);

我需要对其进行规范化,例如,使用Child.Parent和Child.Parent.GrandParent填充IEnumerable <Child>.

势在必行的方式或多或少都很明确.Linq会缩短吗？

在一个查询中更好,对于更多实体,这应该是可扩展的.

我试过像分别创建IEnumerable <GrandParent>,然后IEnumerable <Parent>分配等.

是否可以通过功能方式实现这一点？

Answer 1

Linq 确实做了相反的事情。IE。如果你把它标准化，你可以很容易地说

from g in grandParents
from p in g.Parents
from c in p.Children
select new { GrandParentName = g.Name, ParentName = p.Name, ChildName = c.Name };

做你所要求的事情更加棘手。像这样的东西

var grandparents = (from g in dataSource
                    select new GrandParent {
                        Title = g[0],
                        Parents = (from p in dataSource
                                   where p[0] == g[0]
                                   select new Parent {
                                      Title = p[1],
                                      Children = from c in dataSource
                                                 where p[1] == c[1]
                                                 select new
                                                            {
                                                                Title = c[2]
                                                            }
                                   }).Distinct(new ParentTitleComparer())
                    }).Distinct(new GrandParentTitleComparer());

我不相信这比命令式版本读起来更好。