问题描述
那就是GroupBy运算符。您是否正在使用LINQ to Objects?
这是一个例子:
using System;
using System.Collections.Generic;
using System.Linq;
public class Test
{
static void Main()
{
var users = new[]
{
new { User="Bob", Hobby="Football" },
new { User="Bob", Hobby="Golf" },
new { User="Bob", Hobby="Tennis" },
new { User="Sue", Hobby="Sleeping" },
new { User="Sue", Hobby="Drinking" },
};
var groupedUsers = users.GroupBy(user => user.User);
foreach (var group in groupedUsers)
{
Console.WriteLine("{0}: ", group.Key);
foreach (var entry in group)
{
Console.WriteLine(" {0}", entry.Hobby);
}
}
}
}
这就是分组-您可以自己管理其余的吗?
解决方法
我正在寻找与Sybase的LIST()或MySQL的group_concat()等效的LINQ
它将转换为:
User Hobby
--------------
Bob Football
Bob Golf
Bob Tennis
Sue Sleeping
Sue Drinking
至:
User Hobby
--------------
Bob Football,Golf,Tennis
Sue Sleeping,Drinking