This documentation is archived and is not being maintained.

Solutions as Containers

To enable the integrated development environment (IDE) to apply its wide range of tools, designers, templates, and settings, Visual Studio .NET implements conceptual containers called solutions and projects. A project includes a set of source files, plus related metadata such as component references and build instructions. Projects generally produce one or more output files when built. A solution includes one or more projects, plus files and metadata that help define the solution as a whole:

Visual Studio .NET automatically generates a solution when you create a new project. As needed, you can then add other projects to the solution. Solution Explorer provides a graphical view of the entire solution that helps you manage its projects and files as you develop your application.

You can also create blank solutions without projects. This provides a way to use the Visual Studio .NET editors and designers to modify stand-alone files. Solution Explorer provides additional folders for non-project items


Solutions are designed to manage the way sets of related projects are configured, built, and deployed. Depending upon your requirements, a Visual Studio .NET solution can include just one project, or several projects built jointly by a development team. A complex application might even require multiple solutions.

Use Solution Build Configurations to specify how to build and deploy different versions of your application for specific groups of users. You can, for example, configure debug builds for developers and testers, and retail builds for partners and end users. For further information on creating and using Solution Build Configurations, see Configuration Manager Dialog Box and Default and Custom Builds.


Solutions allow you to concentrate on developing and deploying your projects, instead of sorting through all the details of managing project files, components, and objects. Each Visual Studio .NET solution allows you to:

  • Work on multiple projects within the same instance of the IDE.
  • Work on items using settings and options that apply to an entire set of projects.
  • Use Solution Explorer to help develop and deploy your application.
  • Manage additional files opened outside the context of a solution or project.

Definition Files

Visual Studio .NET stores the definition for a solution in two files: .sln and .suo. In previous versions of Visual Studio, you might have noticed the group (.vbg) or workspace (.dsw) files in Visual Basic 6.0 and Visual C++ 6.0, respectively.

The solution definition file (.sln) stores the metadata that defines your solution:

  • Projects that are associated with the solution.
  • Items available at the solution level that are not associated with a particular project.
  • Solution build configurations that set which project configurations to apply in each type of build.

The metadata stored in the .suo file as you construct a solution and set its properties is used to customize the IDE whenever the solution is active. For example, Solution Explorer displays a Miscellaneous Files folder for a solution if you enable that option, and tools appropriate for the types of projects included in the solution become available from the Toolbox.

See Also

Introduction to Solutions, Projects, and Items | Project Items | Projects as Containers | Solution, Project, and File User Interface Elements | Editing Common Properties for Solutions | Projects and Solutions, Environment, Options Dialog Box | Toolbox