When you save a solution, it's given the file extension .sln (such as WinHello.sln), and all the projects in the solution are saved with the extension .vbproj. Here's a list of the types of file extensions you'll see in files in VB .NET, and the kinds of files they correspond to; the most popular file extension is .vb. This is a useful list, because if VB .NET has added files to your solution that you haven't expected, you often can figure them out by their file extension:

  • .vb-Can be a basic Windows form, a code file, a module file for storing functions, a user control, a data form, a custom control, an inherited form, a Web custom control, an inherited user control, a Windows service, a custom setup file, an image file for creating a custom icon, or an AssemblyInfo file (used to store assembly information such as versioning and assembly name).

  • .xsd-An XML schema provided to create typed datasets.

  • .xml-An XML document file.

  • .htm-An HTML document.

  • .txt-A text file.

  • .xslt-An XSLT stylesheet file, used to transform XML documents and XML schemas.

  • .css-A cascading stylesheet file.

  • .rpt-A Crystal Report.

  • .bmp-A bitmap file.

  • .js-A JScript file (Microsoft's version of JavaScript).

  • .vbs-A VBScript file.

  • .wsf-A Windows scripting file.

  • .aspx-A Web form.

  • .asp-An active server page.

  • .asmx-A Web service class.

  • .vsdisco-A dynamic discovery project; .vsdisco provides a means to enumerate all Web Services and all schemas in a Web project.

  • .web-A Web configuration file, .web configures Web settings for a Web project.

  • .asax-A global application class, used to handle global ASP.NET application-level events.

  • .resx-A resource file used to store resource information.