Environment

This type returns information about the operating system context. It offers commonly-needed properties such as NewLine.

Methods and properties

Environment methods and properties return information about the operating system and execution environment. We test these methods.

Exit

This method does not run finally statements. It provides a way to kill a process in its physical sense on the operating system.

using System;

class Program
{
    static void Main()
    {
        try
        {
            //
            // Calls the Environment.Exit method and returns a zero status code.
            // ... The finally statement is never reached.
            //
            Environment.Exit(0);
        }
        finally
        {
            Console.WriteLine("Finally statement");
        }
    }
}

ExpandEnvironmentVariables

In the Windows operating system environment variables are used. They insert strings specific to the operating system's current setup.

using System;

class Program
{
    static void Main()
    {
        string[] variables =
        {
            "%WINDIR%",
            "%HOMEDRIVE%",
            "%USERNAME%",
            "%COMPUTERNAME%"
        };
        foreach (string v in variables)
        {
            string result = Environment.ExpandEnvironmentVariables(v);
            Console.WriteLine(result);
        }
    }
}
C:\Windows
C:
Sam2
SAM-PC2

GetCommandLineArgs

You can receive command line arguments only in the Main entry point in the C# language. But the GetCommandLineArgs method can be used anywhere.

using System;

class Program
{
    static void Main(string[] args)
    {
        // Args does not contain the program path.
        Console.WriteLine(string.Join(",", args));

        // GetCommandLineArgs contains the program path as the first element.
        string[] array = Environment.GetCommandLineArgs();
        Console.WriteLine(string.Join(",", array));
    }
}
(Argument: dot net perls)
(Second output line truncated.)

dot,net,perls
C:\Users\...\bin\Release\test.exe,dot,net,perls

GetFolderPath

This returns a path string. It receives an enum of type Environment.SpecialFolder. It returns a string that depends on the user's current operating environment.

using System;

class Program
{
    static void Main()
    {
        string path = Environment.GetFolderPath(Environment.SpecialFolder.Desktop);
        Console.WriteLine(path);
    }
}
Varies depending on the operating environment.

C:\Users\Sam2\Desktop

GetLogicalDrives

With this method, you can determine where to search for files on local drives. It returns a string array containing drive volumes.

using System;

class Program
{
    static void Main()
    {
        string[] value = Environment.GetLogicalDrives();
        Console.WriteLine(string.Join(",", value));
    }
}
C:\,D:\,H:\

ProcessorCount

Processors can have multiple cores. The ProcessorCount property in the .NET Framework returns the total number of cores on a computer, not processors.

using System;

class Program
{
    static void Main()
    {
        Console.WriteLine(Environment.ProcessorCount);
    }
}
2

SpecialFolder

Microsoft Windows has special folders. For example, Microsoft Word will save to Documents. We use the Environment.SpecialFolder enum to locate these special folders.

Desktop
DesktopDirectory
MyDocuments
MyMusic
MyPictures
Programs
StartMenu
Startup
public partial class ExampleForm : Form
{
    // Initialize the controls on the form in the constructor here.
    public ExampleForm()
    {
        InitializeComponent();
        openFileDialog1.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
    }
}

GetFolderPath example

SpecialFolder is not restricted to usage with InitialDirectory. GetFolderPath converts the enum into a usable string by the system.

private void TestMethod()
{
    //
    // Store the location of Pictures folder in a string.
    //
    Environment.SpecialFolder special = Environment.SpecialFolder.MyPictures;
    string folderLocation = Environment.GetFolderPath(special);
}

NewLine

On the Windows operating system, the newline is "\r\n". This is two characters. The Environment.NewLine property returns this string literal.

The Environment type is a way to interact with the operating system environment. It eliminates the need to use interoperability calls to get this information.