how do i create new object out of list of object using linq

Question

I do have a list of employee objects which can be 'group by' by employee id.

List<EmployeeHour> employeeHours = new List<EmployeeHour>

{

new EmployeeHour{Id = 1, EmployeeName = "Emp1", Day = 1, Hours = 6},

new EmployeeHour{Id = 1, EmployeeName = "Emp1", Day = 2, Hours = 8},

new EmployeeHour{Id = 2, EmployeeName = "Emp2", Day = 1, Hours = 6},

new EmployeeHour{Id = 2, EmployeeName = "Emp2", Day = 2, Hours = 8}

};

I want to create list of object something like

new {
Id = 1,

EmplyeeName = Emp1,

Day1 = 6,

Day2 = 8
},

new {
Id = 2,

EmplyeeName = Emp2,

Day1 = 6,

Day2 = 8
}

Vinay Singh · Answer

Hi Try the below code. using System; using System.Linq; using System.Collections.Generic; public class Program { public static void Main() { // Student collection List employeeHours = new List { new EmployeeHour{Id = 1, EmployeeName = "Emp1" , Day = 1, Hours = 6}, new EmployeeHour{Id = 1, EmployeeName = "Emp1" , Day = 2, Hours = 8}, new EmployeeHour{Id = 2, EmployeeName = "Emp2" , Day = 1, Hours = 6}, new EmployeeHour{Id = 2, EmployeeName = "Emp2" , Day = 2, Hours = 8} }; var groupedResult = from s in employeeHours group s by s.Id; //iterate each group foreach (var emp in groupedResult) { Console.WriteLine( "Id: {0}" , emp.Key); //Each group has a key foreach (EmployeeHour s in emp) // Each group has inner collection { Console.WriteLine( "Day: {0}" , s.Day); } } } } public class EmployeeHour{ public int Id { get ; set ; } public string EmployeeName { get ; set ; } public int Day { get ; set ; } public int Hours { get ; set ; } } For demo check the link https://www.tutorialsteacher.com/codeeditor?cid=cs-BZnxR2

Jignesh Kumar · Answer

Hi, Please try below one, List employeeHours = new List { new EmployeeHour{Id = 1, EmployeeName = "Emp1" , Day = 1, Hours = 6}, new EmployeeHour{Id = 1, EmployeeName = "Emp1" , Day = 2, Hours = 8}, new EmployeeHour{Id = 2, EmployeeName = "Emp2" , Day = 1, Hours = 6}, new EmployeeHour{Id = 2, EmployeeName = "Emp2" , Day = 2, Hours = 8} }; var groupByEmploueeId = from emp in employeeHours group emp by emp.Id; For you can use below link, https://csharp.net-tutorials.com/linq/grouping-data-the-groupby-method/

Vinay Singh · Answer

Good one ....If your problem is solved then it good.. Happy coding

Istudent Rana · Answer

This is how I did it. Is ther better way to do this? dynamic d = new { Employee = group.FirstOrDefault().EmployeeName, Day1 = group.FirstOrDefault(g => g.DayNumber == 1)?.Hours, Day2 = group.FirstOrDefault(g => g.DayNumber == 2)?.Hours, }; list.Add(d);

Istudent Rana · Answer

@Jignesh, I know that part of grouping the employee but after that i have to project new object such that day 1 is assigned with day 1 hours