Validating and cleaning up strings is a common task in software development. This example shows various ways in which strings can be cleaned up using control chars.
BenchmarkDotNet v0.14.0, Windows 10 (10.0.19045.5131/22H2/2022Update)
AMD Ryzen 9 9950X, 1 CPU, 32 logical and 16 physical cores
.NET SDK 9.0.100
[Host] : .NET 9.0.0 (9.0.24.52809), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
.NET 7.0 : .NET 7.0.20 (7.0.2024.26716), X64 RyuJIT AVX2
.NET 8.0 : .NET 8.0.11 (8.0.1124.51707), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
.NET 9.0 : .NET 9.0.0 (9.0.24.52809), X64 RyuJIT AVX-512F+CD+BW+DQ+VL+VBMI
| Method | Runtime | Mean | Error | StdDev | Ratio | RatioSD | Gen0 | Gen1 | Allocated |
|----------------------- |--------- |-----------:|---------:|--------:|------:|--------:|-------:|-------:|----------:|
| StringBuilder_Pool | .NET 7.0 | 360.8 ns | 1.15 ns | 1.02 ns | 1.26 | 0.01 | 0.0744 | - | 1.22 KB |
| StringBuilder_Pool | .NET 8.0 | 395.2 ns | 2.58 ns | 2.41 ns | 1.38 | 0.01 | 0.0744 | - | 1.22 KB |
| StringBuilder_Pool | .NET 9.0 | 286.5 ns | 2.36 ns | 2.09 ns | 1.00 | 0.01 | 0.0744 | - | 1.22 KB |
| | | | | | | | | | |
| StringBuilder_Instance | .NET 7.0 | 541.3 ns | 8.65 ns | 8.10 ns | 1.50 | 0.02 | 0.2270 | 0.0019 | 3.71 KB |
| StringBuilder_Instance | .NET 8.0 | 494.8 ns | 7.85 ns | 7.34 ns | 1.37 | 0.02 | 0.2270 | 0.0019 | 3.71 KB |
| StringBuilder_Instance | .NET 9.0 | 361.7 ns | 1.12 ns | 0.93 ns | 1.00 | 0.00 | 0.2270 | 0.0019 | 3.71 KB |
| | | | | | | | | | |
| Linq | .NET 7.0 | 3,418.9 ns | 10.44 ns | 9.25 ns | 3.45 | 0.02 | 0.0763 | - | 1.3 KB |
| Linq | .NET 8.0 | 1,103.8 ns | 7.93 ns | 7.03 ns | 1.11 | 0.01 | 0.0782 | - | 1.3 KB |
| Linq | .NET 9.0 | 990.3 ns | 4.88 ns | 4.56 ns | 1.00 | 0.01 | 0.0782 | - | 1.3 KB |
| | | | | | | | | | |
| Span | .NET 7.0 | 249.8 ns | 4.97 ns | 4.88 ns | 1.03 | 0.02 | 0.0744 | - | 1.22 KB |
| Span | .NET 8.0 | 251.4 ns | 3.61 ns | 3.37 ns | 1.04 | 0.02 | 0.0744 | - | 1.22 KB |
| Span | .NET 9.0 | 241.7 ns | 2.22 ns | 2.07 ns | 1.00 | 0.01 | 0.0744 | - | 1.22 KB |
| | | | | | | | | | |
| Span1 | .NET 7.0 | 285.0 ns | 2.78 ns | 2.46 ns | 1.10 | 0.01 | 0.0744 | - | 1.22 KB |
| Span1 | .NET 8.0 | 286.1 ns | 3.51 ns | 3.11 ns | 1.10 | 0.02 | 0.0744 | - | 1.22 KB |
| Span1 | .NET 9.0 | 259.1 ns | 2.66 ns | 2.49 ns | 1.00 | 0.01 | 0.0744 | - | 1.22 KB |
| | | | | | | | | | |
| Span2 | .NET 7.0 | 290.2 ns | 3.76 ns | 3.52 ns | 1.23 | 0.02 | 0.0744 | - | 1.22 KB |
| Span2 | .NET 8.0 | 276.1 ns | 1.10 ns | 1.03 ns | 1.17 | 0.01 | 0.0744 | - | 1.22 KB |
| Span2 | .NET 9.0 | 235.2 ns | 1.53 ns | 1.36 ns | 1.00 | 0.01 | 0.0744 | - | 1.22 KB |
| | | | | | | | | | |
| Span2Unsafe | .NET 7.0 | 232.2 ns | 2.32 ns | 2.17 ns | 1.06 | 0.01 | 0.0744 | - | 1.22 KB |
| Span2Unsafe | .NET 8.0 | 279.1 ns | 1.27 ns | 1.06 ns | 1.27 | 0.01 | 0.0744 | - | 1.22 KB |
| Span2Unsafe | .NET 9.0 | 219.0 ns | 1.07 ns | 1.00 ns | 1.00 | 0.01 | 0.0744 | - | 1.22 KB |- 🚀 Linq is by far the slowest option
- 🚀 A StringBuilder is more performant in comparison; performance can be further improved with StringBuilder pooling
- 🚀 All Span variants are faster by far; as expected, an unsafe implementation is the most efficient.
ReadOnlySpan<char>would cause the double allocation when converted tostringvia ToString.
dotnet run -c Release --framework net9.0- Additional implementation provided by @gfoidl
- 2024/11 - Add .NET 9