k3ldar · k3ldar · Aug 15, 2026 · Aug 15, 2026
diff --git a/CmdLineTest/CmdLineTest.csproj b/CmdLineTest/CmdLineTest.csproj
@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net7.0</TargetFramework>
+    <TargetFramework>net9.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>disable</Nullable>
 	<ExcludeFromCodeCoverage>true</ExcludeFromCodeCoverage>

diff --git a/CmdLineTest/Program.cs b/CmdLineTest/Program.cs
@@ -3,10 +3,10 @@
 
 IConsoleProcessorFactory factory = new ConsoleProcessorFactory();
 
-object[] processors = new object[]
-{
+object[] processors =
+[
     new PluginProcessor(),
-};
+];
 
 IConsoleProcessor consoleProcessor = factory.Create("MyProg", processors);
 

diff --git a/Directory.Build.props b/Directory.Build.props
@@ -2,7 +2,7 @@
   <Import Project="$([MSBuild]::GetPathOfFileAbove('Directory.Build.props', '$(MSBuildThisFileDirectory)../'))"
     Condition="Exists('$(MSBuildThisFileDirectory)..\Directory.Build.props')"/>
   <PropertyGroup>
-	<FrameWorks>net7.0;netstandard2.0</FrameWorks>
+	<FrameWorks>net9.0;netstandard2.0</FrameWorks>
     <RunAnalyzersDuringBuild>true</RunAnalyzersDuringBuild>
     <NoWarn>1701;1702;8032;8981</NoWarn>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
@@ -22,16 +22,16 @@
     <PackageTags>GCode Sender</PackageTags>
     <PackageProjectUrl>http://pluginmanager.website/</PackageProjectUrl>
     <PackageLicenseExpression>GPL-3.0-or-later</PackageLicenseExpression>
-    <PackageReleaseNotes>Supports net7.0</PackageReleaseNotes>
+    <PackageReleaseNotes>Supports net9.0</PackageReleaseNotes>
     <PackageTags>CommandLinePlus - Command line processor for c#</PackageTags>
   </PropertyGroup>
 
   <PropertyGroup>
-    <FrameWorkLatestVersion>net7.0</FrameWorkLatestVersion>
+    <FrameWorkLatestVersion>net9.0</FrameWorkLatestVersion>
   </PropertyGroup>
 
   <PropertyGroup>
-	<AssemblyVersion>2.3.0</AssemblyVersion>
+	<AssemblyVersion>2.4.0</AssemblyVersion>
     <Version>$(AssemblyVersion).0</Version>
 	<FileVersion>$(Version)</FileVersion>
 	<ProductVersion>$(Version)</ProductVersion>
@@ -47,15 +47,15 @@
     <CheckForOverflowUnderflow>True</CheckForOverflowUnderflow>
   </PropertyGroup>
 
-  <PropertyGroup Condition="'$(Configuration)|$(TargetFramework)'=='Debug|net7.0'">
-    <DefineConstants>CODE_ANALYSIS;DEBUG;TRACE;NET_CORE;NET_6_0;NET_6_X;ISO_WEEK;ATTR_OS;NET_5_ABOVE;NET_6_ABOVE;NET_7_ABOVE;NET_7_0;NET_7_X;WIN_SYSTEM</DefineConstants>
+  <PropertyGroup Condition="'$(Configuration)|$(TargetFramework)'=='Debug|net9.0'">
+    <DefineConstants>CODE_ANALYSIS;DEBUG;TRACE;NET_CORE;NET_6_0;NET_6_X;ISO_WEEK;ATTR_OS;NET_5_ABOVE;NET_6_ABOVE;NET_7_ABOVE;NET_8_ABOVE;NET_9_ABOVE;NET_9_0;NET_9_X;WIN_SYSTEM</DefineConstants>
     <CheckForOverflowUnderflow>true</CheckForOverflowUnderflow>
     <DebugType>embedded</DebugType>
     <DebugSymbols>true</DebugSymbols>
   </PropertyGroup>
 
-  <PropertyGroup Condition="'$(Configuration)|$(TargetFramework)'=='Release|net7.0'">
-    <DefineConstants>CODE_ANALYSIS;NET_CORE;NET_6_0;NET_6_X;ISO_WEEK;ATTR_OS;NET_5_ABOVE;NET_6_ABOVE;NET_7_ABOVE;NET_7_0;NET_7_X;WIN_SYSTEM</DefineConstants>
+  <PropertyGroup Condition="'$(Configuration)|$(TargetFramework)'=='Release|net9.0'">
+    <DefineConstants>CODE_ANALYSIS;NET_CORE;NET_6_0;NET_6_X;ISO_WEEK;ATTR_OS;NET_5_ABOVE;NET_6_ABOVE;NET_7_ABOVE;NET_8_ABOVE;NET_9_ABOVE;NET_9_0;NET_9_X;WIN_SYSTEM</DefineConstants>
     <CheckForOverflowUnderflow>true</CheckForOverflowUnderflow>
     <DebugType>embedded</DebugType>
     <DebugSymbols>true</DebugSymbols>

diff --git a/README.md b/README.md
@@ -1,4 +1,4 @@
-# CommandLinePlus
+# CommandLinePlus
 This project started because I needed a command line parser that could:
 
 - Have a primary option
@@ -11,26 +11,28 @@ myprog.exe Option SubOption -param:value
 
 
 #### Supports
-- Net7.0
-- Netstandard2.0
+- .NET 9.0
+- .NET Standard 2.0
 
 #### How it works
 
-Create a class which descends from BaseCommandLine, specify the name (primary option) and create methods (each method is a sub option)
+Create a class which descends from `BaseCommandLine`, specify the `Name` (primary option) and create methods (each method is a sub option).
 
-Add CmdLineDescriptions and CmdLineAbbreviation to methods, properties and processor classes for self describing help information.
+Add `CmdLineDescription` and `CmdLineAbbreviation` attributes to methods, parameters and processor classes for self-describing help information.
 
-In the following example we can these command lines:
+In the following example we can use these command lines:
 
 ```
-myprog.exe Plugin /p:myplugin
+myprog.exe Plugin
 myprog.exe Plugin Add -p:myplugin
 myprog.exe Plugin Remove --p:myplugin
 myprog.exe Plugin Disable /p:myplugin
 myprog.exe Plugin Enable -p:myplugin
 ```
 
 ```
+    using CommandLinePlus;
+
     [CmdLineDescription("Processes plugins for entire application")]
     internal class PluginProcessor : BaseCommandLine, IDisposable
     {
@@ -106,25 +108,79 @@ myprog.exe Plugin Enable -p:myplugin
             throw new NotImplementedException();
         }
     }
+```
+#### Wiring it up
+
+Add a reference to the `CommandLinePlus` package, create your processors, then bootstrap them from the application entry point. The demo (`CmdLineTest`) uses C# top-level statements:
+
+```csharp
+using CmdLineTest;
+
+IConsoleProcessorFactory factory = new ConsoleProcessorFactory();
+
+object[] processors = new object[]
+{
+    new PluginProcessor(),
+};
+
+IConsoleProcessor consoleProcessor = factory.Create("MyProg", processors);
+
+switch (consoleProcessor.Run(out int resultCode))
+{
+    case RunResult.CandidateFound:
+        Console.WriteLine("finished");
+        break;
+
+    case RunResult.DisplayHelp:
+        break;
+
+    default:
+        throw new InvalidOperationException("Didn't work");
+}
 
+return resultCode;
 ```
-#### Available Paramater seperators
-The following characters can be used as param seperators
-- = (equals)
-- : (colon)
-
-#### Available Paramater Idetifiers
-The following are used to identify parameter values
- - (-) (single dash) doesn't need the brackets except in markdown :-\
- - -- (double dash)
- - / (forward slash)
 
-## Devops
-[![CodeQL](https://github.com/k3ldar/CommandLinePlus/actions/workflows/codeql-analysis.yml/badge.svg)](https://github.com/k3ldar/CommandLinePlus/actions/workflows/codeql-analysis.yml) [![SonarCloud](https://github.com/k3ldar/CommandLinePlus/actions/workflows/SonarCloud.yml/badge.svg)](https://github.com/k3ldar/CommandLinePlus/actions/workflows/SonarCloud.yml) [![.NET](https://github.com/k3ldar/CommandLinePlus/actions/workflows/dotnet.yml/badge.svg)](https://github.com/k3ldar/CommandLinePlus/actions/workflows/dotnet.yml)
+The demo project makes the `CommandLinePlus` types available via a global using in its `.csproj`:
+
+```xml
+<Using Include="CommandLinePlus" />
+```
+
+If you don't use that, add `using CommandLinePlus;` to your file instead. The `MyProg` argument passed to `Create` is the process name shown in help; replace it with your application's name.
+
+`Run` returns a `RunResult`:
 
-[![Vulnerabilities](https://sonarcloud.io/api/project_badges/measure?project=k3ldar_CommandLinePlus&metric=vulnerabilities)](https://sonarcloud.io/summary/overall?id=k3ldar_CommandLinePlus) [![Bugs](https://sonarcloud.io/api/project_badges/measure?project=k3ldar_CommandLinePlus&metric=bugs)](https://sonarcloud.io/summary/overalloverall?id=k3ldar_CommandLinePlus) [![Code Smells](https://sonarcloud.io/api/project_badges/measure?project=k3ldar_CommandLinePlus&metric=code_smells)](https://sonarcloud.io/summary/overall?id=k3ldar_CommandLinePlus) [![Technical Debt](https://sonarcloud.io/api/project_badges/measure?project=k3ldar_CommandLinePlus&metric=sqale_index)](https://sonarcloud.io/summary/overall?id=k3ldar_CommandLinePlus)
+| Value | Meaning |
+| --- | --- |
+| `None` | No operation performed (default value) |
+| `DisplayHelp` | Built-in `-?` help was shown |
+| `NotEnoughCandidates` | No processor matched the primary option |
+| `TooManyCandidates` | More than one processor matched the primary option |
+| `DefaultSubOptionUsed` | Sub-option did not match a method, `Execute` was called instead |
+| `InvalidParameters` | A method matched but an argument could not be converted |
+| `CandidateFound` | A sub-option method ran successfully |
 
-[![Reliability Rating](https://sonarcloud.io/api/project_badges/measure?project=k3ldar_CommandLinePlus&metric=reliability_rating)](https://sonarcloud.io/summary/overall?id=k3ldar_CommandLinePlus) [![Maintainability Rating](https://sonarcloud.io/api/project_badges/measure?project=k3ldar_CommandLinePlus&metric=sqale_rating)](https://sonarcloud.io/summary/overall?id=k3ldar_CommandLinePlus) [![Security Rating](https://sonarcloud.io/api/project_badges/measure?project=k3ldar_CommandLinePlus&metric=security_rating)](https://sonarcloud.io/summary/overall?id=k3ldar_CommandLinePlus) 
+#### Built-in options
 
-[![Lines of Code](https://sonarcloud.io/api/project_badges/measure?project=k3ldar_CommandLinePlus&metric=ncloc)](https://sonarcloud.io/summary/new_code?id=k3ldar_CommandLinePlus) [![Coverage](https://sonarcloud.io/api/project_badges/measure?project=k3ldar_CommandLinePlus&metric=coverage)](https://sonarcloud.io/summary/new_code?id=k3ldar_CommandLinePlus)
+- `-?` (or `/?`) shows help for all processors, one processor's sub-options, or a sub-option's parameters.
+- `-v:<level>` (or `/v:<level>`) sets the verbosity level: `0` Quiet, `1` Normal, `2` Diagnostic, `3` Full. The default is `1` (Normal).
 
+#### Parameters
+
+Sub-option methods receive values from command-line parameters. Parameter names are matched case-insensitively, sub-option method names are matched case-insensitively, and the primary option name is case-sensitive by default.
+
+- `bool`, `int`, `enum` and `Guid` values are converted automatically.
+- Parameters with a default value are optional.
+- A method may return `void` or `int`; an `int` result becomes the process exit code.
+
+#### Available parameter separators
+The following characters can be used as parameter separators
+- `=` (equals)
+- `:` (colon)
+
+#### Available parameter identifiers
+The following are used to identify parameter values
+- `-` (single dash)
+- `--` (double dash)
+- `/` (forward slash)
diff --git a/src/CommandLinePlus.csproj b/src/CommandLinePlus.csproj
@@ -15,7 +15,7 @@
     <GeneratePackageOnBuild>True</GeneratePackageOnBuild>
     <Title>Command line plus</Title>
     <PackageReadmeFile>readme.md</PackageReadmeFile>
-    <PackageReleaseNotes>Supports netstandard2.0 and net7.0</PackageReleaseNotes>
+    <PackageReleaseNotes>Supports netstandard2.0 and net9.0</PackageReleaseNotes>
     <EnforceCodeStyleInBuild>True</EnforceCodeStyleInBuild>
     <EnableNETAnalyzers>True</EnableNETAnalyzers>
     <AnalysisLevel>latest-all</AnalysisLevel>
@@ -25,6 +25,7 @@
 myprog.exe Option Sub -p1:test /p3:test</Description>
     <PackageProjectUrl>https://github.com/k3ldar/CommandLinePlus</PackageProjectUrl>
     <RepositoryUrl>https://github.com/k3ldar/CommandLinePlus</RepositoryUrl>
+    <Copyright>Copyright (c) 2022 - 2026 Simon Carter.  All rights reserved.</Copyright>
   </PropertyGroup>
 
   <PropertyGroup Condition="'$(Configuration)|$(Platform)' == 'Debug|x86'">
@@ -91,7 +92,7 @@ myprog.exe Option Sub -p1:test /p3:test</Description>
   </ItemGroup>
 
   <ItemGroup>
-    <None Include="readme.md" Pack="true" PackagePath=""/>
+    <None Include="readme.md" Pack="true" PackagePath="" />
   </ItemGroup>
 
   <Target Name="PostBuild" AfterTargets="PostBuildEvent" Condition="'$(Configuration)|$(CodeSignAssembly)'=='Release|true'">

diff --git a/src/Internal/CommandLineArguments.cs b/src/Internal/CommandLineArguments.cs
@@ -113,7 +113,7 @@ public string[] AllArguments()
                 args.Add($"{item.Key}={item.Value}");
             }
 
-            return args.ToArray();
+            return [.. args];
         }
 
         #endregion ICommandLine Methods

diff --git a/src/Internal/ConsoleDisplay.cs b/src/Internal/ConsoleDisplay.cs
@@ -1,21 +1,34 @@
 using System;
 using System.Globalization;
 using System.Runtime.CompilerServices;
+using System.Text;
 
 using static CommandLinePlus.Constants;
 
 namespace CommandLinePlus.Internal
 {
     internal sealed class ConsoleDisplay : IDisplay
     {
+#if NET9_0_OR_GREATER
+        private static readonly CompositeFormat DisplayInnerExceptionFormat = CompositeFormat.Parse(DisplayInnerException);
+#endif
+
         public ConsoleDisplay(ICommandLineArguments arguments)
         {
+#if NET9_0_OR_GREATER
+            ArgumentNullException.ThrowIfNull(arguments);
+#else
             if (arguments == null)
                 throw new ArgumentNullException(nameof(arguments));
+#endif
 
             Verbosity = (VerbosityLevel)arguments.Get<int>(Constants.CmdLineSettingVerbosity, 1);
 
+#if NET9_0_OR_GREATER
+            if (!Enum.IsDefined(Verbosity))
+#else
             if (!Enum.IsDefined(typeof(VerbosityLevel), Verbosity))
+#endif
                 Verbosity = VerbosityLevel.Normal;
         }
 
@@ -34,7 +47,11 @@ public void Write(Exception exception)
 
             if (exception.InnerException != null)
             {
-                InternalWriteLine(String.Format(CultureInfo.InvariantCulture, DisplayInnerException, exception.InnerException.GetType().Name));
+                #if NET9_0_OR_GREATER
+                                InternalWriteLine(String.Format(CultureInfo.InvariantCulture, DisplayInnerExceptionFormat, exception.InnerException.GetType().Name));
+                #else
+                                InternalWriteLine(String.Format(CultureInfo.InvariantCulture, DisplayInnerException, exception.InnerException.GetType().Name));
+                #endif
                 InternalWriteLine(exception.InnerException.Message);
                 LineCount++;
             }
@@ -90,8 +107,12 @@ public void WriteLine(VerbosityLevel verbosityLevel, string message, params obje
             if (String.IsNullOrEmpty(message))
                 throw new ArgumentNullException(nameof(message));
 
-            if (args == null)
-                throw new ArgumentNullException(nameof(args));
+            #if NET9_0_OR_GREATER
+                        ArgumentNullException.ThrowIfNull(args);
+            #else
+                        if (args == null)
+                            throw new ArgumentNullException(nameof(args));
+            #endif
 
             string formattedMessage = String.Format(CultureInfo.InvariantCulture, message, args);