小编Osc*_*rez的帖子

不确定我做错了什么。我一直在互联网上寻找如何使用 lambda 有效地获取基于另一个属性的属性值列表。

假设我有一个包含教师姓名和房间 ID 的教室列表：

public class ClassRoom
{
    public string Teacher;
    public int RoomId;

}

List<ClassRoom> classRooms = new List<ClassRoom>();

classRooms.Add(new ClassRoom() { RoomId = 2000, Teacher = "Mr. Taylor" });
classRooms.Add(new ClassRoom() { RoomId = 2010, Teacher = "Mrs. Lee" });
classRooms.Add(new ClassRoom() { RoomId = 3050, Teacher = "Mrs. McNamara" });
classRooms.Add(new ClassRoom() { RoomId = 4090, Teacher = "Mr. Taylor" });

然后，我需要一个特定老师的房间 ID 列表。

List<int> RoomIds = new List<int>();

    foreach(ClassRoom classRoom in classRooms)
    {
        if(classRoom.Teacher …