Overview

SlnGen is a Visual Studio solution file generator. Visual Studio solutions generally do not scale well for large project trees. They are scoped views of a set of projects.

Enterprise-level builds use custom logic like traversal to convey how they should be built by a hosted build environment. Maintaining Visual Studio solutions becomes hard because you have to keep them in sync with the other build logic.

SlnGen reads the project references of a given project to create a Visual Studio solution on demand. For example, you can run it against a unit test project and be presented with a Visual Studio solution containing the unit test project and all of its project references. You can also run SlnGen against a traversal project in a rooted folder to open a Visual Studio solution containing that view of your project tree.

Getting Started

Download and install the latest version of Visual studio 2022. See Installation guide

SlnGen can be installed as a .NET Core global tool. To do this, please install .NET Core 8.0 or above and run the following command:

dotnet tool install --global Microsoft.VisualStudio.SlnGen.Tool

Once installed, the command slngen is added to your PATH so its available in any command window.

You can invoke the tool using the following command: slngen
Tool 'microsoft.visualstudio.slngen.tool' (version '11.3.5') was successfully installed.

See the frequently asked questions if you are having any issues.

Command-Line Reference

Usage: slngen [options] <project path>

Arguments:
  project path                        An optional path to a project which can include wildcards like **\*.csproj or directories which contain projects files. If not specified, all projects in the current directory will be used.

Options:
  -ab|--alwaysbuild <true>            Always include the project in the build even if it has no matching configuration. Default: true
  -bl|--binarylogger[:<parameters>]   Serializes all build events to a compressed binary file.
                                      By default the file is in the current directory and named "slngen.binlog" and contains the source text of project files, including all imported projects and target files encountered during the build. The optional ProjectImports switch controls this behavior:

                                       ProjectImports=None - Don't collect the project imports.
                                       ProjectImports=Embed - Embed project imports in the log file.
                                       ProjectImports=ZipFile - Save project files to output.projectimports.zip where output is the same name as the binary log file name.

                                      NOTE: The binary logger does not collect non-MSBuild source files such as .cs, .cpp etc.

                                      Example: -bl:output.binlog;ProjectImports=ZipFile
  --collapsefolders <true>            Enables folders containing a single item to be collapsed into their parent folder. Default: false
  -c|--configuration <values>         Specifies one or more Configuration values to use when generating the solution.
  -cl|--consolelogger[:<parameters>]  Parameters to console logger. The available parameters are:
                                          PerformanceSummary--Show time spent in tasks, targets and projects.
                                          Summary--Show error and warning summary at the end.
                                          NoSummary--Don't show error and warning summary at the end.
                                          ErrorsOnly--Show only errors.
                                          WarningsOnly--Show only warnings.
                                          ShowTimestamp--Display the Timestamp as a prefix to any message.
                                          ShowEventId--Show eventId for started events, finished events, and messages
                                          ForceNoAlign--Does not align the text to the size of the console buffer
                                          DisableConsoleColor--Use the default console colors for all logging messages.
                                          ForceConsoleColor--Use ANSI console colors even if console does not support it
                                          Verbosity--overrides the -verbosity setting for this logger (see Microsoft.Build.Framework.LoggerVerbosity enum).
                                       Example:
                                          --consolelogger:PerformanceSummary;NoSummary;Verbosity=Minimal
  -vs|--devenvfullpath                Specifies a full path to Visual Studio's devenv.exe to use when opening the solution file. By default, SlnGen will launch the program associated with the .sln file extension.
  -e|--exclude <values>               Specifies one or more paths to exclude when searching for project files.
  -fl|--filelogger[:<parameters>]     Provides any extra parameters for file loggers. The same parameters listed for the console logger are available.
                                      Some additional available parameters are:
                                          LogFile--path to the log file into which the build log will be written.
                                          Append--determines if the build log will be appended to or overwrite the log file.Setting the switch appends the build log to the log file;
                                              Not setting the switch overwrites the contents of an existing log file. The default is not to append to the log file.
                                          Encoding--specifies the encoding for the file, for example, UTF-8, Unicode, or ASCII
                                          Verbosity--overrides the -verbosity setting for this logger (see Microsoft.Build.Framework.LoggerVerbosity enum).
                                       Examples:
                                          --filelogger:LogFile=MyLog.log;Append;Verbosity=Diagnostic;Encoding=UTF-8
  --folders <true>                    Enables the creation of hierarchical solution folders. Default: false
  --ignoreMainProject                 None of the projects receive special treatment.
  --launch <true|false>               Launch Visual Studio after generating the Solution file. Default: true on Windows and macOS
  --loadprojects <false>              When launching Visual Studio, opens the specified solution without loading any projects. Default: true
  --logger                            Use this logger to log events from SlnGen. To specify multiple loggers, specify each logger separately.
                                      The <logger> syntax is:
                                        [<class>,]<assembly>[;<parameters>]
                                      The <logger class> syntax is:
                                        [<partial or full namespace>.]<logger class name>
                                      The <logger assembly> syntax is:
                                        {<assembly name>[,<strong name>] | <assembly file>}
                                      Logger options specify how SlnGen creates the logger. The <logger parameters> are optional, and are passed to the logger exactly as you typed them.
                                      Examples:
                                        -logger:XMLLogger,MyLogger,Version=1.0.2,Culture=neutral
                                        -logger:XMLLogger,C:\Loggers\MyLogger.dll;OutputAsHTML
  --nologo                            Do not display the startup banner and copyright message.
  --nowarn                            Suppress all warning messages
  --platform <values>                 Specifies one or more Platform values to use when generating the solution.
  -p|--property <name=value[;]>       Set or override these project-level properties. <name> is the property name, and <value> is the property value. Use a semicolon or a comma to separate multiple properties, or specify each property separately.
                                        Example:
                                          --property:WarningLevel=2;MyProperty=true
  -d|--solutiondir <path>             An optional path to the directory in which the solution file will be generated. Defaults to the same directory as the project. --solutionfile will take precedence over this switch.
  -o|--solutionfile <path>            An optional path to the solution file to generate. Defaults to the same directory as the project.
  -v|--verbosity                      Display this amount of information in the event log. The available verbosity levels are:
                                        q[uiet], m[inimal], n[ormal], d[etailed], and diag[nostic].
  --version                           Display version information only.
  --vsversion                         Specifies that a version of Visual Studio should be included in the solution file. When specified with no value, the value will be set to the version of Visual Studio that is used to open the solution.
  -?|-h|--help                        Show help information.

Getting Started (MSBuild Target)

SlnGen is an MSBuild target so you will need to add a <PackageReference /> to all projects that you want use it with. We recommend that you simply add the PackageReference to a common import like Directory.Build.props

<ItemGroup>
  <PackageReference Include="Microsoft.VisualStudio.SlnGen" Version="<Latest Version>" />
</ItemGroup>

Once a project is referencing the NuGet package, you launch SlnGen with MSBuild.exe by running the SlnGen target.

C:\Projects\src\ProjectA.UnitTests>MSBuild.exe /Target:SlnGen /Verbosity:Minimal /NoLogo
  Loading project references...
  Generating Visual Studio solution "C:\Projects\src\ProjectA.UnitTests\ProjectA.UnitTests.sln"...

By default, Visual Studio is launched and opens your generated solution file.

MSBuild Property Reference

The following properties only apply when using SlnGen as an MSBuild target.

Property Description Values Default
SlnGenLaunchVisualStudio Indicates whether or not Visual Studio should be launched to open the solution file after it is generated. true or false true
SlnGenSolutionFileFullPath Specifies the full path to the Visual Studio solution file to generate. By default, the path is the same as the project.   ProjectPath.sln
SlnGenDevEnvFullPath Specifies a full path to Visual Studio’s devenv.exe to use when opening the solution file. By default, SlnGen will launch the program associated with the .sln file extension. However, in some cases you may want to specify a custom path to Visual Studio.    
SlnGenGlobalProperties Specifies MSBuild properties to set when loading projects and project references.   DesignTimeBuild=true;BuildingProject=false
SlnGenVSVersion Specifies a Visual Studio version to include in the generated solution. “default” or a version number  
SlnGenInheritGlobalProperties Indicates whether or not all global variables specified when loading the initial project should be passed around when loading project references. true or false true
SlnGenGlobalPropertiesToRemove Specifies a list of inherited global properties to remove when loading projects.    
SlnGenBinLog Indicates whether or not SlnGen should emit a binary log. true or false false

Command-line argument

MSBuild.exe /Target:SlnGen /Property:"SlnGenLaunchVisualStudio=false"
                           /Property:"SlnGenDevEnvFullPath=%VSINSTALLDIR%Common7\IDE\devenv.exe"

MSBuild properties

<PropertyGroup>
  <SlnGenLaunchVisualStudio>false</SlnGenLaunchVisualStudio>
  <SlnGenSolutionFileFullPath>$(MSBuildProjectDirectory)\$(MSBuildProjectName).sln</SlnGenSolutionFileFullPath>
  <SlnGenGlobalProperties>DoNotDoSomethingWhenLoadingProjects=true;TodayIsYesterday=false</SlnGenGlobalProperties>
  <SlnGenInheritGlobalProperties>false</SlnGenInheritGlobalProperties>
  <SlnGenGlobalPropertiesToRemove>Property1;Property2</SlnGenGlobalPropertiesToRemove>
</PropertyGroup>

Configuring SlnGen

Read more below to learn how to configure the behavior of SlnGen to fit your needs.

Customize the Solution File

Use the following properties and items to customize the generated Solution file.

Property Description Values Default
IncludeInSolutionFile Indicates whether or not a project should be included in a generated Solution file. true or false true
SlnGenFolders Indicates whether or not a hierarchy of folders should be created. If false, the projects are in a flat list. true or false false
SlnGenIsDeployable Indicates whether or not a project is considered deployable by Visual Studio. true or false false
Service Fabric projects are automatically set to true
SlnGenSolutionFolder Specifies a solution folder to place the project in. SlnGenFolders must be false.    
SlnGenProjectName Specifies the display name of the project in the solution.   Project file name without file extension
SlnGenVerbosity Specifies the amount of information to display in the event log when using slngen for the particular solution. Quiet, Minimal, Normal, Detailed, and Diagnostic Normal
SlnGenPlatform Specifies an additional platform to use when generating the solution.    
SlnGenConfiguration Specifies an additional configuration to use when generating the solution.    
Item Description
SlnGenSolutionItem Specifies a file to include as a solution item.
SlnGenProjects Specifies a project to include in the solution. 
<PropertyGroup>
  <!-- Exclude .sqlproj projects from generated solution files -->
  <IncludeInSolutionFile Condition="'$(MSBuildProjectExtension)' == '.sqlproj'">false</IncludeInSolutionFile>

  <!-- Disable folder hierarchy in Solution files, projects will be in a flat list instead -->
  <SlnGenFolders>false</SlnGenFolders>

  <SlnGenVerbosity>Minimal</SlnGenVerbosity>
  <SlnGenPlatform>AnyCPU</SlnGenPlatform>
  <SlnGenConfiguration>Debug;Release</SlnGenConfiguration>
</PropertyGroup>

<ItemGroup>
  <SlnGenSolutionItem Include="$(MSBuildThisFileDirectory)global.json" />
  <SlnGenSolutionItem Include="$(MSBuildThisFileDirectory)README.md" />
  <SlnGenProjects Include="..\..\..\UnitTests\UnitTests.csproj" />
</ItemGroup>

Custom Project Types

SlnGen knows about the following project types:

To add to this list or override an item, specify an SlnGenCustomProjectTypeGuid item in your projects.

Item Description
SlnGenCustomProjectTypeGuid Specifies a file extension and project type GUID. The format of the extension must be “.ext”
Metadata Description
ProjectTypeGuid Specifies the project type GUID to use in the Visual Studio solution. It can be in any GUID format that .NET can parse. 
<ItemGroup>
  <SlnGenCustomProjectTypeGuid Include=".myproj" ProjectTypeGuid="{e05dcbd8-5478-4b75-bbdb-3a3a2e743ff2}" />
  <SlnGenCustomProjectTypeGuid Include=".aproj" ProjectTypeGuid="{bb9d1d44-b292-4016-9ce0-27ea600e8e1c}" />
</ItemGroup>

Extensibility

You can extend SlnGen with the following properties:

Property Description
CustomBeforeSlnGenTargets Specifies a path to a custom MSBuild file to import before SlnGen.targets is imported. This can be useful to set certain properties, items, or targets before SlnGen’s logic is imported.
CustomAfterSlnGenTargets Specifies a path to a custom MSBuild file to import after SlnGen.targets is imported. This can be useful to set certain properties, items, or targets after SlnGen’s logic is imported.