C# a组列表<；对象>；进入列表<；列表<；对象>&燃气轮机；

我如何使用

LINQ

对

a
按
Person.Age
列出人员
并创建新的
按年龄列出人员

public class Person
{
    public string Name;
    public int Age
}

一个
GroupBy
和几个
ToList
调用应该可以完成这项工作：

List<Person> persons = ...;
List<List<Person>> byAge = persons
                           .GroupBy(p => p.Age)
                           .Select(ps => ps.ToList())
                           .ToList();

列出人员=。。。；
按年龄列出=人
.GroupBy（p=>p.Age）
.Select（ps=>ps.ToList（））
.ToList（）；
A
GroupBy
和几个
ToList
调用应该可以完成以下任务：

List<Person> persons = ...;
List<List<Person>> byAge = persons
                           .GroupBy(p => p.Age)
                           .Select(ps => ps.ToList())
                           .ToList();

列出人员=。。。；
按年龄列出=人
.GroupBy（p=>p.Age）
.Select（ps=>ps.ToList（））
.ToList（）；
一种可能的解决方案如下所示：

var persons = new List<Person>
{
    new Person { Age = 20 },
    new Person { Age = 30 },
    new Person { Age = 20 },
    new Person { Age = 40 },
    new Person { Age = 50 },
    new Person { Age = 50 },
    new Person { Age = 20 }
};

var result =    from person in persons
                group person by person.Age into g
                select g.ToList();
var listOfListOfPersons = result.ToList();

var result =    from person in persons
                group person by person.Age into g
                select new Persons
                {
                    Entries = g.ToList()
                };
var listOfListOfPersons = result.ToList();

然后像这样填充它：

var persons = new List<Person>
{
    new Person { Age = 20 },
    new Person { Age = 30 },
    new Person { Age = 20 },
    new Person { Age = 40 },
    new Person { Age = 50 },
    new Person { Age = 50 },
    new Person { Age = 20 }
};

var result =    from person in persons
                group person by person.Age into g
                select g.ToList();
var listOfListOfPersons = result.ToList();

var result =    from person in persons
                group person by person.Age into g
                select new Persons
                {
                    Entries = g.ToList()
                };
var listOfListOfPersons = result.ToList();

一种可能的解决方案如下所示：

var persons = new List<Person>
{
    new Person { Age = 20 },
    new Person { Age = 30 },
    new Person { Age = 20 },
    new Person { Age = 40 },
    new Person { Age = 50 },
    new Person { Age = 50 },
    new Person { Age = 20 }
};

var result =    from person in persons
                group person by person.Age into g
                select g.ToList();
var listOfListOfPersons = result.ToList();

var result =    from person in persons
                group person by person.Age into g
                select new Persons
                {
                    Entries = g.ToList()
                };
var listOfListOfPersons = result.ToList();

然后像这样填充它：

var persons = new List<Person>
{
    new Person { Age = 20 },
    new Person { Age = 30 },
    new Person { Age = 20 },
    new Person { Age = 40 },
    new Person { Age = 50 },
    new Person { Age = 50 },
    new Person { Age = 20 }
};

var result =    from person in persons
                group person by person.Age into g
                select g.ToList();
var listOfListOfPersons = result.ToList();

var result =    from person in persons
                group person by person.Age into g
                select new Persons
                {
                    Entries = g.ToList()
                };
var listOfListOfPersons = result.ToList();

你为什么需要列表？@albertjan我这里有更好的选择吗？你为什么需要列表？@albertjan我这里有更好的选择吗？想解释一下什么不起作用吗？这里很好用。你在foreach循环中试过这个吗？想解释一下什么不起作用吗？它在这里工作得很好。你在foreach循环中尝试过这个吗？Ad 1）为什么你需要匿名类型来只保存一个项目？@MarcinJuraszek修复了它-删除了匿名对象。谢谢。广告1）为什么你需要匿名类型才能保存一件物品？@MarcinJuraszek修复了它-删除了匿名对象。谢谢