# What is the difference between keywords const and readonly in C#?

CsharpProgrammingServer Side Programming

## Const

Constant fields are the fields that cannot be modified. At the time of declaration, you need to assign a value to it.

const int a = 5;

A Read-only field is initialized at the time of declaration or you can also set it within the constructor.

Let us see an example in which the read-only field is initialized inside the constructor −

## Example

class Calculate {
}