C#

Say you’re closing out the register at a Denver bike shop, and the cashier typed an unknown number of sales before typing done. You can’t know the count up front, and that’s exactly the job of a while loop in C#: it repeats a block for as long as a condition stays true. In this … Read more >>

5! is 5 x 4 x 3 x 2 x 1 = 120. A factorial program in C# starts a long at 1 and multiplies it by every number from 2 to n. For 0 and 1 the loop never runs, so you get 1. In this tutorial, I’ll cover the factorial program in C# … Read more >>

Four stores, six months, one grid: that’s what our Phoenix regional manager asked for. A for loop in C# repeats code a set number of times with a counter: for (int i = 0; i < n; i++) { … }. In this tutorial, I’ll show you, one small step at a time, how the … Read more >>

To write functions in C#, you declare a method: a return type, a name, parameters in parentheses and a body. C# calls every function a method, and in a .NET 10 file-based app you can write one right next to your top-level code: Quick answer: use a static method when it only needs its parameters, … Read more >>

The first bug most beginners hit with variables in C# isn’t a crash. It’s a build that refuses to start, because a local variable might be read before it has a value: Quick answer: give it a value on every path, like decimal discount = 0m;. Below, I run that fix and the rest of … Read more >>

Every variable you declare picks one of the data types in C#, and they come in two families. Value types like int, double, decimal, bool and char hold the data itself; reference types like string, object and arrays hold a reference to it: It prints: Below, the sizes and ranges come straight from sizeof and … Read more >>

Say you’re coding accounts for a small Columbus, Ohio credit union. Checking pays a $5 fee under $1,500, savings earns 3% a year, and nobody may type a balance in directly. Those rules map straight onto the OOPs concepts in C#: a class for the account, encapsulation to guard the balance, inheritance and polymorphism for … Read more >>

C# (pronounced “C sharp”) is Microsoft’s free, general-purpose programming language for building web apps, APIs, cloud services, desktop apps and Unity games. You write C#, and the .NET platform compiles and runs it on Windows, macOS and Linux. In this tutorial, I’ll explain what is C# in plain English, then have you write and run … Read more >>

Is 97 prime? A prime number program in C# answers that by trying divisors: return false below 2, return n == 2 for even numbers, then test odd divisors while i <= n / i. If none divides evenly, it’s prime. In this tutorial, I’ll grow one small PrimeTools class step by step, the way … Read more >>

Need to turn “Albuquerque” into “euqreuqublA”? To reverse a string in C#, copy it with ToCharArray(), flip the copy with Array.Reverse(), and wrap it in new string(…). C# strings don’t have a built-in Reverse() method, so that three-step pattern is the standard answer. In this tutorial, I’ll cover seven ways to reverse a string in … Read more >>