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Environment.GetEnvironmentVariable Method (String)

Retrieves the value of an environment variable from the current process.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

public static string GetEnvironmentVariable(
	string variable


Type: System.String

The name of the environment variable.

Return Value

Type: System.String
The value of the environment variable specified by variable, or null if the environment variable is not found.


variable is null.


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");		
		DirectoryInfo info = new DirectoryInfo(".");
			Console.WriteLine("Directory Info:   "+info.FullName);

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