.NET Framework 去查查看
示例
var persons = new[] {
new { Name="Fizz", Job="Developer"},
new { Name="Buzz", Job="Developer"},
new { Name="Foo", Job="Astronaut"},
new { Name="Bar", Job="Astronaut"},
};
var groupedByJob = persons.ToLookup(p => p.Job);
foreach(var theGroup in groupedByJob)
{
Console.WriteLine(
"{0} are {1}s",
string.Join(",", theGroup.Select(g => g.Name).ToArray()),
theGroup.Key);
}
//Fizz，Buzz是开发人员
//Foo，Bar是宇航员