使用groupby对复杂集合进行分组 [英] Grouping a complex collection using groupby

问题描述

我在查询中处理以下结果集。查询结果是动物的集合。每个Animal都可以分配给多个团队。

查询结果

ID TYPE TEAMCODE

2 MAMMAL RTB1

2 MAMMAL RTB2



我可以产生以下输出，但它只是包括第一个AnimalTeamCode RTB1

I am dealing with the following result set in my query. The query result is a collection of Animals. Each Animal can be allocated to more than one team.
Query Result
ID TYPE TEAMCODE
2 MAMMAL RTB1
2 MAMMAL RTB2

I can produce the following output but it only includes the first AnimalTeamCode RTB1

<Animal id="2">
 <AnimalTeam>
   <AnimalTeamCode>RTB1</AnimalTeamCode>
 <AnimalTeam>
<animal>

我想要实现的是每只动物，如果是分配给多个团队我希望像这样显示：

What i am trying to achieve is that for each Animal, if its been allocated to more than one team i want to show it like this:

<Animal id="2">
 <AnimalTeam>
   <AnimalTeamCode>RTB1</AnimalTeamCode>
   <AnimalTeamCode>RTB2</AnimalTeamCode>
 <AnimalTeam>
<animal>

我尝试过：



目前这是我如何使用GroupBy运算符

What I have tried:

currently this how i am using the GroupBy operator

//code to get the listOfAnimals
 ......
 //Group the list of Animals
var groupedCollection = listOfAnimals.GroupBy(animal => animal.ID).ToDictionary(animal => animal.key, animal => animal.Value.ToList())

我如何对结果进行分组以便我可以实现上述目标？

How can i group the results so i can achieve the above?

推荐答案

您没有正确执行此操作，您需要在使用ToDictionary时设置Key和Value属性，只需将ToDictionary调用更改为：

You are not doing it correctly, you need to set the Key and Value property while using ToDictionary, just change the ToDictionary call to be like:

var groupedCollection = listOfAnimals.GroupBy(animal => animal.ID)
                                     .ToDictionary( group => group.Key, 
                                                    group => group.ToList()
                                                   );

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