在c#中对包含嵌套IEnumerable的对象使用linq

public class Department
{
    public string Name { get; set; }
    public IEnumerable<Employee> Employees { get; set; }
}

public class Employee
{
    public string Name { get; set; }
    public int Age { get; set; }
}

var departments = new List<Department>
{
    new Department
    {
        Name = "IT",
        Employees = new List<Employee>
        {
            new Employee { Name = "Alice", Age = 25 },
            new Employee { Name = "Bob", Age = 35 }
        }
    },
    new Department
    {
        Name = "HR",
        Employees = new List<Employee>
        {
            new Employee { Name = "Charlie", Age = 40 }
        }
    }
};

var result = departments.SelectMany(d => d.Employees
    .Where(e => e.Age > 30)
    .Select(e => new { DepartmentName = d.Name, EmployeeName = e.Name }));

foreach (var item in result)
{
    Console.WriteLine($"Department: {item.DepartmentName}, Employee: {item.EmployeeName}");
}