Select 列表中一周没有休息日的记录<T> - C#

Question

我有一个 Employee class 定义如下：

Employee
{
   public int Id { get; set; }
   public string Name { get; set; }
   public DateTime WorkDate { get; set; }
   public bool isOff { get; set; }
}

这是我的 class 实现和用法：

List<Employee> workers = new List<Employee>()
{
    new Employee { Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/11/2016"), IsOff = false},
    new Employee { Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/12/2016"), IsOff = false},
    new Employee { Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/13/2016"), IsOff = true},
    new Employee { Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/14/2016"), IsOff = false},
    new Employee { Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/15/2016"), IsOff = false},
    new Employee { Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/16/2016"), IsOff = false},
    new Employee { Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/17/2016"), IsOff = false},
    new Employee { Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/11/2016"), IsOff = false},
    new Employee { Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/12/2016"), IsOff = false},
    new Employee { Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/13/2016"), IsOff = false},
    new Employee { Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/14/2016"), IsOff = false},
    new Employee { Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/15/2016"), IsOff = false},
    new Employee { Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/16/2016"), IsOff = false},
    new Employee { Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/17/2016"), IsOff = false},
};

在上面的初始化中只有1条记录是关闭的：

Id = 1, Name = "Emp 1" and the WorkDate = 4/13/2016

现在如何获取整个星期（4 月 11 日至 17 日）没有休息日的员工的 ID？即 Id = 2

LINQ 解决方案要好得多，但我不知道该怎么做。

UPDATED

为了避免混淆对象 Employee 我将其更改为 EmployeeSchedule

class EmployeeSchedule
{
   public int Id { get; set; }
   public string Name { get; set; }
   public DateTime WorkDate { get; set; }
   public bool isOff { get; set; }
}

这是实现

List<EmployeeSchedule> workers = new List<EmployeeSchedule>()
{
    new EmployeeSchedule{ Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/11/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/12/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/13/2016"), IsOff = true},
    new EmployeeSchedule{ Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/14/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/15/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/16/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 1, Name = "Emp 1", WorkDate = Convert.ToDateTime("4/17/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/11/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/12/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/13/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/14/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/15/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/16/2016"), IsOff = false},
    new EmployeeSchedule{ Id = 2, Name = "Emp 2", WorkDate = Convert.ToDateTime("4/17/2016"), IsOff = false},
};

所选答案仍然适用。

Answer 1

试试，你有两个条件 ID 和日期，但你的 ID 足以满足你的要求，

List<string> resEmp = new List<string>();

foreach (var item in workers )
 {
     if (item.Id == 2 and item.IsOff == false)
      {
        resEmp.Add(item);
      }
 }

Answer 2

这意味着你需要 fromDate、toDate，你必须从列表中找到员工，条件是 WorkDate 应该在 [=11] 之间=] 和 toDate，还有 isOff == false 意思是 has no day off throughout the week 所以你可以使用下面的代码片段：

 DateTime fromDate = new DateTime(2016, 04, 11);
 DateTime toDate = new DateTime(2016, 04, 17);
 var noDayOfList = workers.GroupBy(x=> x.Id)
                          .Where(x =>
                                 x.All(y=> 
                                 y.WorkDate >= fromDate && 
                                 y.WorkDate <= toDate && 
                                 !y.isOff))
                          .Select(z=>z.Key).ToList();

Answer 3

Now how can i get the id of an employee which has no day off throughout the week (from April 11-17)? Which is Id = 2

您可以使用 Linq 扩展来实现这一点。

var empid = workers.GroupBy(g=> g.Id)           
                   .Where(x=>x.All(e=>!e.IsOff))
                   .Select(x=>x.Key)

Answer 4

你可以这样写：

var startDate = new DateTime(2016,04,11);
var endDate = new DateTime(2016,04,17);

var ids = workers
    .Where(w => w.WorkDate >= startDate)
    .Where(w => w.WorkDate <= endDate)
    .GroupBy(w => w.Id)
    .Where(g => !g.Any(w => w.IsOff))
    .Select(g => g.Key);

本质上：

过滤您需要的行（在此时间范围内）
按员工编号分组
确保组中的 none 行标记为 IsOff
Select 分组键（在本例中，它将是员工的 ID）

不过请注意，调用对象 Employee 有点令人困惑，因为它实际上代表员工的日程安排，而不是员工本身

Answer 5

也看看这些代码。

我已经定义了一个 Employee 模型 class 来获取数据，

也许目前您需要 Id，但将来您也可以使用其他属性。

public class Employee
    {
        public int Id { get; set; }
        public string Name { get; set; }
        public DateTime WorkDate { get; set; }
        public bool IsOff { get; set; }
    }

和带有 Linq 表达式的代码，

 Employee objEmployee = new Employee();
 objEmployee.Id = workers
         .GroupBy(itm => itm.Id)
         .Where(itm => !itm.Any(m => m.IsOff))
         .Select(itm => itm.Key)
         .FirstOrDefault();

Select 列表中一周没有休息日的记录<T> - C#

Select records which has no day-off throughout the week in List<T> - C#

c#

linq

ienumerable

enumerable