C# Error CS0238 – ‘member’ cannot be sealed because it is not an override

C# Compiler Error

CS0238 – ‘member’ cannot be sealed because it is not an override

Reason for the Error

You will receive this error in your C# program when you have used the sealed keyword for a method without override,

sealed keyword on a class prevents other classes from inheriting from it. The sealed modifier on a method can be used on a method that overrides a virtual method in a base class.

For example, try to compile the below code snippet.

namespace DeveloperPubNamespace
{
    abstract class BaseEmployee
    {
        public abstract void SetId();
    }
    class Employee : BaseEmployee
    {
        public sealed void SetId()
        { 
        }
    }
    class Program
    {
        public static void Main()
        {
        }
    }
}

This program will result with the C# error code CS0238 because the SetId() is marked as sealed without override.

Error CS0238 ‘Employee.SetId()’ cannot be sealed because it is not an override DeveloperPublish C:\Users\SenthilBalu\source\repos\ConsoleApp3\ConsoleApp3\Program.cs 9 Active

Solution

To fix the error code CS0238 in C#, you should mark the method as sealed override instead of just sealed.

namespace DeveloperPubNamespace
{
    abstract class BaseEmployee
    {
        public abstract void SetId();
    }
    class Employee : BaseEmployee
    {
        public sealed override void SetId()
        { 
        }
    }
    class Program
    {
        public static void Main()
        {
        }
    }
}