Program:

The source code to calculate the total of employee's salaries using the Aggregate() method, is given below. The given program is compiled and executed successfully on Microsoft Visual Studio.

//C# program to calculate the total of employee's salary 
//using the Aggregate() method. 

using System;
using System.Linq;
using System.Collections.Generic;

public class Employee
{
    int ID;
    string Name;
    int Salary;
    string Department;

    static void Main(string[] args)
    {
        int TotalSalary = 0;

        List<Employee> employees = new List<Employee>()
        {
             new Employee {ID=101,   Name="Amit  "    , Salary=4000,Department="ABC"},
             new Employee {ID=102,   Name="Amit  "    , Salary=3000,Department="XYZ"},
             new Employee {ID=103,   Name="Salman"    , Salary=3000,Department="ABC"},
             new Employee {ID=104,   Name="Ram   "    , Salary=2000,Department="XYZ"},
             new Employee {ID=105,   Name="Shyam "    , Salary=7000,Department="ABC"},
             new Employee {ID=106,   Name="Kishor"    , Salary=5000,Department="XYZ"},
        };

        TotalSalary=employees.Aggregate<Employee, int>(0, (sum, e) => sum += e.Salary);

        Console.WriteLine("Total Salary : "+TotalSalary);
    }
}

Output:

Total Salary : 24000
Press any key to continue . . .

Explanation:

In the above program, we created the Employee class that contains the ID, Name, Salary, Department, and Main() method. In the Main() method, we created a list of employees.

TotalSalary=employees.Aggregate<Employee, int>(0, (sum, e) => sum += e.Salary);

In the above statement, we calculated the total of all employee's salaries using the Aggregate() method and then print the total of salary on the console screen.