C#中如何獲取系統環境變量等

C#中獲取系統環境變量需要用到Environment 類。

其中提供了有關當前環境和平台的信息以及操作它們的方法。該類不能被繼承

以下代碼得到%systemdrive%的值，即“C:”

string sPath = Environment.GetEnvironmentVariable("systemdrive");
Console.WriteLine(sPath);

更多使用方法：

//--------------獲取當前程序信息
//當前程序啟動的命令，字符串
Console.WriteLine("CommandLine:{0}", Environment.CommandLine);
string[] arguments = Environment.GetCommandLineArgs();
Console.WriteLine("GetCommandLineArgs:{0}", string.Join(", ", arguments));
//獲取當前程序目錄
Console.WriteLine("CurrentDirectory:{0}", Environment.CurrentDirectory);
//獲取當前程序，工作的物理內存大小
Console.WriteLine("WorkingSet: {0}", Environment.WorkingSet);
//退出碼
Console.WriteLine("ExitCode:{0}", Environment.ExitCode);
//獲取當前程序是否開機啟動
Console.WriteLine("HasShutdownStarted: {0}", Environment.HasShutdownStarted);
//獲取當前跟蹤信息
Console.WriteLine("StackTrace: '{0}'", Environment.StackTrace);
//獲取換行符
Console.WriteLine("NewLine: {0}  first line{0}  second line{0}  third line",
                Environment.NewLine);

//--------------獲取當前用戶信息
//當前用戶的域名稱
Console.WriteLine("UserDomainName: {0}", Environment.UserDomainName);
//當前用戶是否交互
Console.WriteLine("UserInteractive: {0}", Environment.UserInteractive);
//當前用戶名稱
Console.WriteLine("UserName: {0}", Environment.UserName);

//--------------獲取當前系統信息
//獲取當前計算機名稱
Console.WriteLine("MachineName: {0}", Environment.MachineName);
//獲取系統鏡像等版本
Console.WriteLine("Version: {0}", Environment.Version.ToString());
//獲取當前操作系統版本
Console.WriteLine("OSVersion: {0}", Environment.OSVersion.ToString());
//獲取當前系統目錄
Console.WriteLine("GetFolderPath: {0}",
                Environment.GetFolderPath(Environment.SpecialFolder.System));
//獲取當前計算機邏輯磁盤名稱列表
String[] drives = Environment.GetLogicalDrives();
Console.WriteLine("GetLogicalDrives: {0}", String.Join(", ", drives));
//獲取系統目錄
String str;
String nl = Environment.NewLine;
String query = "My system drive is %SystemDrive% and my system root is %SystemRoot%";
str = Environment.ExpandEnvironmentVariables(query);
Console.WriteLine("ExpandEnvironmentVariables: {0}  {1}", nl, str);
//獲取系統臨時文件夾
Console.WriteLine("GetEnvironmentVariable: {0}  My temporary directory is {1}.", nl,
                        Environment.GetEnvironmentVariable("TEMP"));

//--------------遍歷所有信息
Console.WriteLine("GetEnvironmentVariables: ");
IDictionary environmentVariables = Environment.GetEnvironmentVariables();
foreach (DictionaryEntry de in environmentVariables)
{
    Console.WriteLine("  {0} = {1}", de.Key, de.Value);
}