使用Linq创建嵌套组和子列表

// 假设有一个包含员工信息的集合
List<Employee> employees = GetEmployees();

// 使用Linq查询创建嵌套组和子列表
var nestedGroups = employees.GroupBy(e => e.Department)
                            .Select(g => new
                            {
                                Department = g.Key,
                                Employees = g.ToList()
                            });

// 遍历嵌套组和子列表
foreach (var group in nestedGroups)
{
    Console.WriteLine("Department: " + group.Department);
    foreach (var employee in group.Employees)
    {
        Console.WriteLine("Employee: " + employee.Name);
    }
    Console.WriteLine();
}