c# - 使用 lambda 从主从列表中选择详细信息

Question

下面是我的示例数据。两家公司有两名员工。

List<Company> companies = new List<Company> 
{
    new Company
    {
        Name = "ABC Company",
        Address = "No.1 St. USA",
        Employees = new List<Employee> { new Employee { Name = "John", Age = 30 }, new Employee { Name = "David", Age = 20 } }
    },
    new Company
    {
        Name = "DEF Company",
        Address = "No.2 St. USA",
        Employees = new List<Employee> { new Employee { Name = "Michael", Age = 22 }, new Employee { Name = "Jason", Age = 27 } }
    }
};

我尝试使用以下语法检索所有员工:

var employees = companies.Select(c => c.Employees).ToList();

但是，它给了我

The name 'employees' does not exist in the current context

当我在运行时观看它时。我的预期结果是 List<Employee>拥有所有4名员工。任何建议将不胜感激。

Answer 1

您应该使用 SelectMany 而不是 Select。

您显示的错误与该查询无关。很可能您在尝试查看此变量时不在正确的范围内。