Understanding Environment Variables in C#

The Environment class also provides some useful methods.

ExpandEnvironmentVariables	Replaces the name of each environment variable embedded in the specified string with the string equivalent of the value of the variable, then returns the resulting string.
GetCommandLineArgs	Returns a string array containing the command line arguments for the current process.
GetEnvironmentVariable	Returns the value of the specified environment variable.
GetEnvironmentVariables	Returns all environment variables and their values.
GetFolderPath	Gets the path to the system special folder identified by the specified enumeration.
GetLogicalDrives	Returns an array of string containing the names of the logical drives on the current computer.

The following code displays the machine information and logical drives of a machine.

using System;   
class EnvironmentClass  
{  
    static void Main(string[] args)  
    {  
        //Getting machine and user information  
        Console.WriteLine("Machine Information");  
        Console.WriteLine("======================");  
        Console.WriteLine("Machine Name: "+ Environment.MachineName);  
        Console.WriteLine("OS Version: "+ Environment.OSVersion);  
        Console.WriteLine("System Directory: "+ Environment.SystemDirectory);  
        Console.WriteLine("User Name: "+ Environment.UserName);  
        Console.WriteLine("Version: "+ Environment.Version);  
        Console.WriteLine("Current Directory: "+ Environment.CurrentDirectory);  
        Console.WriteLine();             
        // Get all logical hard drives             
        string[] drives = Environment.GetLogicalDrives();  
        Console.WriteLine("======================");  
        Console.WriteLine("Available drives:");  
        foreach(string drive in drives)  
              Console.WriteLine(drive);  
        Console.ReadLine();  
    }  
}