Retrieves the value of an environment variable from the current process.
(in mscorlib.dll)
Visual Basic (Declaration)
Public Shared Function GetEnvironmentVariable ( _
variable As String _
) As String
Dim variable As String
Dim returnValue As String
returnValue = Environment.GetEnvironmentVariable(variable)
public static string GetEnvironmentVariable(
string variable
)
public:
static String^ GetEnvironmentVariable(
String^ variable
)
public static function GetEnvironmentVariable(
variable : String
) : String
Return Value
Type:
System..::.StringThe value of the environment variable specified by variable, or nullNothingnullptra null reference (Nothing in Visual Basic) if the environment variable is not found.
| Exception | Condition |
|---|
| ArgumentNullException |
variable is nullNothingnullptra null reference (Nothing in Visual Basic). |
| SecurityException | The caller does not have the required permission to perform this operation. |
Environment variable names are not case-sensitive.
The following code example demonstrates the GetEnvironmentVariable method.
' Change the directory to %WINDIR%
Environment.CurrentDirectory = Environment.GetEnvironmentVariable("windir")
Dim info As New DirectoryInfo(".")
Console.WriteLine(("Directory Info: " + info.FullName))
// Change the directory to %WINDIR%
Environment.CurrentDirectory = Environment.GetEnvironmentVariable("windir");
DirectoryInfo info = new DirectoryInfo(".");
lock(info)
{
Console.WriteLine("Directory Info: "+info.FullName);
}
// Change the directory to %WINDIR%
Environment::CurrentDirectory = Environment::GetEnvironmentVariable( "windir" );
DirectoryInfo^ info = gcnew DirectoryInfo( "." );
System::Threading::Monitor::Enter( info );
try
{
Console::WriteLine( "Directory Info: {0}", info->FullName );
}
finally
{
System::Threading::Monitor::Exit( info );
}
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
.NET Framework
Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
Reference