About
In this code snippet, we will learn about constants in C#.
A constant is a variable that is marked with the const keyword. Such a variable can only have its value set once at compile-time, after that it can’t be changed anymore.
Note: There are also readonly variables, see how they differ from const here.
Let’s have a look at the code below to see how to declare a constant variable.
Code:
using System;
namespace constants
{
class Program
{
static void Main(string[] args)
{
int a = 10;
//The variable b is a constant and can't be changed after being assigned.
const int b = 15;
a = 5;
//If we try this we will get an exception.
//b = 10;
Console.WriteLine("a: " + a + " b:" + b);
Console.ReadLine();
}
}
}





