Using Records In C# 9.0

using System;
namespace ConsoleAppRecords
{
    public class Program
    {
        static void Main(string[] args)
        {
            // Classes
            var employeeClass = new EmployeeClass();
            employeeClass.Id = 1;
            employeeClass.EmpName = "John Smith";
            employeeClass.Salary = 1000;
            var secondEmployeeClass = new EmployeeClass();
            secondEmployeeClass.Id = 1;
            secondEmployeeClass.EmpName = "John Smith";
            secondEmployeeClass.Salary = 1000;
            Console.WriteLine(employeeClass == secondEmployeeClass
                ? "employeeClass is equal to secondEmployeeClass"
                : "employeeClass is not equal to secondEmployeeClass");

            // Records
            var employeeRecord = new Employee();
            employeeRecord.Id = 1;
            employeeRecord.EmpName = "John Smith";
            employeeRecord.Salary = 1000;
            var secondEmployeeRecord = new Employee();
            secondEmployeeRecord.Id = 1;
            secondEmployeeRecord.EmpName = "John Smith";
            secondEmployeeRecord.Salary = 1000;
            var thirdEmployeeRecord = new Employee();
            thirdEmployeeRecord.Id = 2;
            thirdEmployeeRecord.EmpName = "John Smith";
            thirdEmployeeRecord.Salary = 1000;
            Console.WriteLine(employeeRecord == secondEmployeeRecord
                ? "employeeRecord is equal to secondEmployeeRecord"
                : "employeeRecord is not equal to secondEmployeeRecord");
            Console.WriteLine(employeeRecord == thirdEmployeeRecord
                ? "employeeRecord is equal to thirdEmployeeRecord"
                : "employeeRecord is not equal to thirdEmployeeRecord");
            // Updating Records
            var updatedEmployee = employeeRecord with
            {
                Salary = 2000
            };
            Console.WriteLine(employeeRecord == updatedEmployee
                ? "employeeRecord is equal to updatedEmployee"
                : "employeeRecord is not equal to updatedEmployee");

            Console.ReadKey();
        }
    }
    public record Employee
    {
        public int Id { get; set; }
        public string EmpName { get; set; }
        public double Salary { get; set; }
    }
    public class EmployeeClass
    {
        public int Id { get; set; }
        public string EmpName { get; set; }
        public double Salary { get; set; }
    }
}

In the above code, we first create two classes with the same values for each member. However, these will not be returned as equal as they point to separate references.

Then, we create two records in which the members have the same values. These will be returned as equal. For further testing, we create a third record that has a member (Id) with a different value. Now, when we compare this record with the first one, they are considered different as the values of the members are not the same.

Finally, we see how to create a new record from an existing one with a value of one member changed. This will create a new record, and the old one will have the same previous value. We can then compare and see that they are considered different.

We can execute the code and confirm our results.

Summary

In this article, we looked at records which are a new feature in C# 9.0. The main advantage of using records is that they are immutable and, when passed in a state to some function, are guaranteed to stay in the same state. Happy Coding.