C# 根据不同类的计数对对象列表进行降序排序

我被困在这个问题上，需要根据其他列表进行降序排序。Llstu名称需要按年龄递减进行更新

public class Test
{
    public String Name;
    public Int32 Age;
}

List<String> l_lstNames = new List<String> { "A1", "A3", "A2", "A4", "A0" };

List<Test> l_lstStudents = new List<Test> 
{ 
    new Test { Age = 33, Name = "A0" }, 
    new Test { Age = 10, Name = "A1" }, 
    new Test { Age = 50, Name = "A2" }, 
    new Test { Age = 8,  Name = "A3" }, 
    new Test { Age = 25, Name = "A4" }, 
};

// Output
List<String> l_lstNames = new List<String> { "A2", "A0", "A4", "A1", "A3" };

找到了一些sames样本，但与我要找的不匹配。感谢您的帮助。

创建具有名称到年龄映射的词典，并在order方法中使用它：

var dict = students.ToDictionary(x => x.Name, x => x.Age);

var ordered = source.OrderByDescending(x => dict[x.Name]).ToList();

或者，您可以只订购students collection，然后选择Name only：

---

如果只希望名称按降序排列：

var sorted = l_lstStudents           // From the list of students
    .OrderByDescending(l => l.Age)   // with the oldest student first
    .Select(s => s.Name)             // give me just the names
    .ToList();                       // in a list!

---

我想这就是你要找的

List<String> l_lstNames1 = (from student in l_lstStudents
                          where l_lstNames.Any(a => student.Name == a)
                          orderby student.Age descending
                          select student.Name ).ToList();

或

---

+1以获取简明示例和所需输出。完美的可能副本！事实上，我的学生名单是在dict和它只是你的一行代码得到解决方案！谢谢，谢谢。这也帮助了我。

List<String> l_lstNames1 = (from student in l_lstStudents
                          where l_lstNames.Any(a => student.Name == a)
                          orderby student.Age descending
                          select student.Name ).ToList();

List<String> l_lstNames2 = l_lstStudents.OrderByDescending(a => a.Age)
                                .Where(a => l_lstNames.Any(b => b == a.Name))
                                .Select(a => a.Name).ToList();