C# EnvironmentVariableTarget枚舉代碼示例

本文整理匯總了C#中System.EnvironmentVariableTarget枚舉的典型用法代碼示例。如果您正苦於以下問題：C# EnvironmentVariableTarget枚舉的具體用法？C# EnvironmentVariableTarget怎麽用？C# EnvironmentVariableTarget使用的例子？那麽, 這裏精選的枚舉代碼示例或許可以為您提供幫助。

在下文中一共展示了EnvironmentVariableTarget枚舉的1個代碼示例，這些例子默認根據受歡迎程度排序。您可以為喜歡或者感覺有用的代碼點讚，您的評價將有助於係統推薦出更棒的C#代碼示例。

示例1: Main

//引入命名空間
using System;
using System.Collections;
using Microsoft.Win32;

class Sample 
{
    public static void Main() 
    {
        // Environment variable names for default, process, user, and machine targets.
        string defaultEnvVar = nameof(defaultEnvVar);
        string processEnvVar = nameof(processEnvVar);
        string userEnvVar = nameof(userEnvVar);
        string machineEnvVar = nameof(machineEnvVar);

        string dft = nameof(dft);
        string process = nameof(process);
        string user = nameof(user);
        string machine = nameof(machine);

        // Set the environment variable for each target.
        Console.WriteLine("Setting environment variables for each target...\n");
        // The default target (the current process).
        Environment.SetEnvironmentVariable(defaultEnvVar, dft);
        // The current process.
        Environment.SetEnvironmentVariable(processEnvVar, process, 
                                           EnvironmentVariableTarget.Process);
        // The current user.
        Environment.SetEnvironmentVariable(userEnvVar, user, 
                                           EnvironmentVariableTarget.User);
        // The local machine.
        Environment.SetEnvironmentVariable(machineEnvVar, machine, 
                                           EnvironmentVariableTarget.Machine);

        // Define an array of environment variables.
        string[] envVars = { defaultEnvVar,processEnvVar, userEnvVar, machineEnvVar };
        
        // Try to get the environment variables from each target.
        // The default (no specified target).
        Console.WriteLine("Retrieving environment variables from the default target:");
        foreach (var envVar in envVars)
        {
          var value = Environment.GetEnvironmentVariable(envVar) ?? "(none)";
          Console.WriteLine($"   {envVar}: {value}");
        }
        // The process block.
        Console.WriteLine("\nRetrieving environment variables from the Process target:");
        foreach (var envVar in envVars)
        {
          var value = Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.Process) ?? "(none)";
          Console.WriteLine($"   {envVar}: {value}");
        }
        // The user block.
        Console.WriteLine("\nRetrieving environment variables from the User target:");
        foreach (var envVar in envVars)
        {
          var value = Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.User) ?? "(none)";
          Console.WriteLine($"   {envVar}: {value}");
        }
        // The machine block.
        Console.WriteLine("\nRetrieving environment variables from the Machine target:");
        foreach (var envVar in envVars)
        {
          var value = Environment.GetEnvironmentVariable(envVar, EnvironmentVariableTarget.Machine) ?? "(none)";
          Console.WriteLine($"   {envVar}: {value}");
        }

        // Delete the environment variable for each target.
        Console.WriteLine("\nDeleting environment variables for each target...\n");
        // The default target (the current process).
        Environment.SetEnvironmentVariable(defaultEnvVar, null);
        // The current process.
        Environment.SetEnvironmentVariable(processEnvVar, null, 
                                           EnvironmentVariableTarget.Process);
        // The current user.
        Environment.SetEnvironmentVariable(userEnvVar, null, 
                                           EnvironmentVariableTarget.User);
        // The local machine.
        Environment.SetEnvironmentVariable(machineEnvVar, null, 
                                           EnvironmentVariableTarget.Machine);
    }
}

開發者ID:.NET開發者，項目名稱:System，代碼行數:82，代碼來源:EnvironmentVariableTarget

輸出：

Setting environment variables for each target...

Retrieving environment variables from the default target:
defaultEnvVar: dft
processEnvVar: process
userEnvVar: user
machineEnvVar: (none)

Retrieving environment variables from the Process target:
defaultEnvVar: dft
processEnvVar: process
userEnvVar: user
machineEnvVar: (none)

Retrieving environment variables from the User target:
defaultEnvVar: (none)
processEnvVar: (none)
userEnvVar: user
machineEnvVar: (none)

Retrieving environment variables from the Machine target:
defaultEnvVar: (none)
processEnvVar: (none)
userEnvVar: (none)
machineEnvVar: machine

Deleting environment variables for each target...

The example displays the following output if run on a Unix-based system:

Setting environment variables for each target...

Retrieving environment variables from the default target:
defaultEnvVar: dft
processEnvVar: process
userEnvVar: (none)
machineEnvVar: (none)

Retrieving environment variables from the Process target:
defaultEnvVar: dft
processEnvVar: process
userEnvVar: (none)
machineEnvVar: (none)

Retrieving environment variables from the User target:
defaultEnvVar: (none)
processEnvVar: (none)
userEnvVar: (none)
machineEnvVar: (none)

Retrieving environment variables from the Machine target:
defaultEnvVar: (none)
processEnvVar: (none)
userEnvVar: (none)
machineEnvVar: (none)

Deleting environment variables for each target...

注：本文中的System.EnvironmentVariableTarget枚舉示例由純淨天空整理自Github/MSDocs等開源代碼及文檔管理平台，相關代碼片段篩選自各路編程大神貢獻的開源項目，源碼版權歸原作者所有，傳播和使用請參考對應項目的License；未經允許，請勿轉載。