.NET Reference Guide

Managing Windows Forms Applications

Last updated Jul 16, 2004.

The System.Windows.Forms.Application class provides methods and properties that allow you to manage Windows Forms applications and obtain information about the application's runtime environment.

Data Paths and Registry Keys

Whereas the System.Environment class contains properties and methods that provide information about the system in general and is available from all types of .NET programs, Application class is available only to Windows Forms applications and the information provide applies specifically to the executing program. For example, if you call the System.Environment.GetFolderPath method to obtain the common application data path (System.Environment.SpecialFolder.CommonApplicationData), the returned value will be the base directory for all common application data. A typical value for would be "C:\Documents and Settings\All Users\Application Data". System.Windows.Forms.Application.CommonAppDataPath, on the other hand, returns the directory containing common data for the specific application. For example, in a Windows Forms program called "formsInfo", the returned value would be "C:\Documents and Settings\All Users\Application Data\Hackers, Inc.\formsInfo\1.0.5.200". In this path name, "Hackers, Inc.", "formsInfo", and the version number (1.0.5.200) are the values that are entered in the application's AssemblyInfo.cs (AssemblyInfo.vb) file for the AssemblyCompany, AssemblyProduct, and AssemblyVersion attributes.

The Application class contains the following path and registry entry properties, all of which follow the same naming schema: company\product\version:

• CommonAppDataPath gets the path for application data that is shared among all users of the current application.

• CommonAppDataRegistry gets the registry key for application data that is shared among all users of the application.

• LocalUserAppDataPath gets the path where the local, non-roaming user will store data for this application.

• UserAppDataPath gets the path to store application data for this user that will be available in the user's roaming profile.

• UserAppDataRegistry gets the registry key for user-specific application data.

Two other paths will be of interest to some programs: ExecutablePath and StartupPath. ExecutablePath gets the fully-qualified path name of the executing program. For example, "D:\MyProgram\bin\Debug\MyProgram.exe". StartupPath returns the path of the directory that contains the executable program. Given the previous example, that would be "D:\MyProgram\bin\Debug". StartupPath is poorly named, as it could be confused with the program's initial working directory, a value that you can set in the shortcut properties dialog box.