Types, Variables, and Constants in C# - Example You Can Run Online

Introduction

C# checks types at compile time while var asks the compiler to infer a type from the assigned value.

const creates a compile-time constant. var remains statically typed; price is still a decimal and cannot later hold unrelated data.

Runnable C# example

C#

Run code →

Program.cs

using System;

class Program
{
    static void Main()
    {
        const decimal TaxRate = 0.10m;
        var price = 25.00m;
        int quantity = 4;
        decimal total = price * quantity * (1 + TaxRate);
        Console.WriteLine($"Total: {total:C}");
    }
}

Result of running the code

Total: ¤110.00

Practice with the debugger

Set a breakpoint on an important assignment or condition, click Debug, and inspect the local values before stepping to the next line.

Practice with a challenge

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