Author: csharp.academy

StringBuilder performance can be improved in C# by setting its capacity

When using StringBuilder in .NET most of times we likely just use the default constructor StringBuilder()… BUT if we have a rough estimate of how long our final string will be setting the capacity to this estimate can improve performance of StringBuilder dramatically. StringBuilder performance in C# is improved when setting capacity because StringBuilder doesn’t … Continue reading StringBuilder performance can be improved in C# by setting its capacity

.NET 6 string concatenation performance benchmarks

Since there’s been so many amazing performance improvements in .NET 6 I thought it would be fun to compare different .NET string concatenation approaches to see which is the best performing and which is the most memory efficient. Below are benchmarks taken using BenchmarkDotNet for a simple scenario of just adding 4 strings with spacers … Continue reading .NET 6 string concatenation performance benchmarks

C#9 new AND, OR, NOT pattern matching keywords

C#9 (released Nov 2020) has some pattern matching enhancements. Added in C#9 (among other pattern changes) is conjunctive patterns (AND keyword), disjunctive patterns (OR keyword) and negative patterns (NOT keyword). Two examples are below. These are simple examples of course but basically you don’t have to repeat the variable name as before and the syntax … Continue reading C#9 new AND, OR, NOT pattern matching keywords

Using C# indices and range syntax to access elements in a sequence

Microsofts Indices and Ranges page provides examples of the indices and range syntax available in C# (introduced in C#8). This syntax provides a succinct way to access single elements or ranges in a sequence. The first example below shows the ‘index from the end’ operator ^, which gives us a shorthand way of getting items relative … Continue reading Using C# indices and range syntax to access elements in a sequence

Using ToLower() or ToUpper() in C# to compare strings is not safe in all cultures

If you’re using Resharper, Roslynator or similar you’ll likely see string comparisons using ToLower() or ToUpper() flagged. Why are these C# string compare methods flagged? Well these string comparisons are not safe in all cultures. The canonical example is the ‘Turkish i problem‘ which relates to how in Turkish the dot is present on the … Continue reading Using ToLower() or ToUpper() in C# to compare strings is not safe in all cultures

Don’t use the C# var keyword everywhere in your code just to be consistent

Don’t use the var keyword everywhere in your code base just to be consistent. If using var removes clarity for certain assignments its best not to use it in these cases. Example 1 below shows some usages of var in which the type is very clear from the right hand side. In these cases var … Continue reading Don’t use the C# var keyword everywhere in your code just to be consistent

Easier immutability with Init only properties in C# 9

C# 9 shipped with .NET 5 in November. One change included is init only properties which allow us to have immutable (non-changeable) classes without some of the downsides associated with pre C# 9 approaches. As can be seen below in C# 8 we’d typically have getters with no setters which gives us immutability…great.. but it … Continue reading Easier immutability with Init only properties in C# 9