Question

我有以下列表。

List<Employee> employees = new List<Employee>() 
{
    new Employee { EmpID = 1 , Name ="AC", DateofPresentation=newDateTime(2013,12,24),new List<Employee>{}                
    new Employee { EmpID = 1 , Name ="AC", DateofPresentation=newDateTime(2013,12,23),      new List<Employee>{}        
    new Employee { EmpID = 1 , Name ="AC", DateofPresentation=newDateTime(2013,12,22),new List<Employee>{}

}

我需要像这样排序。我有一张表格，显示特定的员工数据。我需要将项目显示为像UI这样的父项。所以我需要这个子列表。

 List<Employee> employees = new List<Employee>() 
{
    new Employee
        { 
          EmpID = 1 , Name ="AC", DateofPresentation=newDateTime(2013,12,24),
          new list<Employee>
           { 
              new Employee { EmpID = 1 , Name ="AC"  DateofPresentation=newDateTime(2013,12,23), new List<Employee>{}
              new Employee { EmpID = 1 , Name ="AC", DateofPresentation=newDateTime(2013,12,22), new List<Employee>{}

           }  
}

我需要将最近过时的员工作为父母进行排序，并将其他员工排在列表中

我可以在linq中实现这个目标吗？

Answer 1

以下是代码解决方案：

    List<Employee> employees = new List<Employee>() 
    {
        new Employee() { EmpID = 1 , Name ="AC", DateofPresentation=new DateTime(2013,12,24)},
        new Employee() { EmpID = 1 , Name ="AC", DateofPresentation=new DateTime(2013,12,23)},
        new Employee() { EmpID = 1 , Name ="AC", DateofPresentation=new DateTime(2013,12,22)},
        new Employee() { EmpID = 1 , Name ="AC", DateofPresentation=new DateTime(2013,12,21)},
        new Employee() { EmpID = 2 , Name ="AC", DateofPresentation=new DateTime(2013,12,25)},
        new Employee() { EmpID = 2 , Name ="AC", DateofPresentation=new DateTime(2013,12,21)}
    };


    var list = employees.
        Select(i => new Employee()
        {
            EmpID = i.EmpID,
            Name = i.Name,
            DateofPresentation = i.DateofPresentation,
            Employees = employees.Where(j => i.EmpID == j.EmpID && j.DateofPresentation < i.DateofPresentation).ToList()
        }).
            GroupBy(x => x.EmpID).
            Select(g => g.OrderByDescending(i => i.DateofPresentation).First()).
            ToList();

Answer 2

您需要将一个属性（我称之为Others）添加到Employee以存储列表

employees
    .GroupBy(x => x.EmpID)
    .Select(g => {
        var byPres = g.OrderByDescending(x => x.DateofPresentation).ToArray();
        var e = byPres.First();
        e.Others = byPres.Skip(1).ToList();
        return e;
    })

参见演示https://dotnetfiddle.net/kRiMds

移动列表中列表的重复项c＃

2 个答案: