Turning a C# list into a comma separated string takes one line: string.Join(“, “, cities). It turns Austin, Dallas, Houston and El Paso into one string you can drop into a label, a log line or an email. In this tutorial, I’ll take one small US customer list through every C# list to comma separated … Read more >>

Airport codes, state abbreviations and 20-character receipt lines all need the start of a string. To get the first N characters of a string in C#, call s.Substring(0, n), or use the range s[..n] on C# 8 and later. In this tutorial, I’ll line up the options for the C# get first N characters of … Read more >>

Two warehouse bin counts got keyed into the wrong slots, and you need to flip them. To swap two numbers in C#, write (a, b) = (b, a); or use a temp variable. Both are safe, and the tuple version fits on one line: In this tutorial, I’ll compare every way to swap two numbers … Read more >>

If you need to print or log an object, Console.WriteLine(order) is the obvious first try, and it prints Bookstore.Order instead of the order. That’s the default ToString in C#: unless a type overrides it, it returns the type’s full name. The fix is to override ToString() in your class (or use a record), and to … Read more >>

Say you run checkout for a Denver outdoor store, and marketing changes the discount every week: 10% off one week, $15 off orders over $100 the next. Delegates in C# handle that cleanly. A delegate is a type-safe variable that holds a method, so checkout calls whichever rule you plug in at run time, with … Read more >>

Our code reviews still catch MAX_CART_ITEMS in new C# code, usually from developers who came from Java, Python or C. Quick answer: the C# constant naming convention is PascalCase for every const, whether it’s public, private or local, with no underscore prefix: I tested this in a .NET 10 checkout for a Texas outdoor store, … Read more >>

This is the enum I flag most often in code reviews, and it breaks three C# enum naming conventions at once: an Enum suffix, ALL_CAPS members and the type name repeated inside every value. The fix is enum OrderStatus { Pending, Shipped, Delivered }: a singular PascalCase type with plain PascalCase members. Below are the … Read more >>

Nobody enjoys typing a long folder path. In a C# Windows Forms app, the folder browser dialog fixes that: create a FolderBrowserDialog, call ShowDialog(), and read SelectedPath when it returns DialogResult.OK. In this tutorial, I’ll put together a Report Exporter for a small Seattle accounting firm and use the folder browser dialog in C# three … Read more >>

Log files pile up fast, and sooner or later your C# app has to clean them up. To delete a file in C#, call File.Delete(path) from System.IO. It removes the file and quietly does nothing if the file isn’t there. In this tutorial, I’ll build a small log-cleanup console tool step by step and cover … Read more >>