Operators & Expressions

🔷 C# Programming Lesson 3 Beginner

Operators perform operations on variables and values. C# includes arithmetic, comparison, logical, and increment operators.

1 Arithmetic division and Operator precedence

Math evaluations match standard precedence rules. Modulus (`%`) yields the remainder of a division. Dividing two integers yields a truncated integer: `5 / 2` evaluates to `2`. Cast one to double to retain decimals: `(double)5 / 2` yields `2.5`.

2 Logical Short-Circuiting

C# uses logical operators: `&&` (AND), `||` (OR), and `!` (NOT). Short-circuiting skips evaluating the second condition if the first condition determines the outcome. Let's test these operators:

C# — Operators ▶ Run Code

using System;

class Program {
    static void Main() {
        int a = 10;
        int b = 4;

        Console.WriteLine("Truncated Division (10/4): " + (a / b));
        Console.WriteLine("Double Cast Division: " + ((double)a / b));

        // Increment postfix vs prefix
        int x = 5;
        int y = x++; // y gets 5, then x becomes 6
        Console.WriteLine("Postfix: y=" + y + ", x=" + x);

        int p = 5;
        int q = ++p; // p becomes 6, then q gets 6
        Console.WriteLine("Prefix: q=" + q + ", p=" + p);
    }
}

3 Code Challenge

Challenge: Initialize `int score = 80`. Use comparison and logical operators to check if the score is greater than 50, less than or equal to 100, and is even. Print the result.