以前实现系统环境变量设置时是要在电脑属性--高级--环境变量设置，实现方式主要有2种，
- 修改注册表，添加环境变量
- 调用系统Kernel32.DLL函数，设置环境变量
注册表方式，是要修改注册表的位置是[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment]
代码我已经封装，注意要引入命名空间
using Microsoft.Win32; using System.Runtime.InteropServices;
如下：
class SysEnvironment
{
/// <summary>
/// 获取系统环境变量
/// </summary>
/// <param name="name"></param>
/// <returns></returns>
public static string GetSysEnvironmentByName(string name)
{
string result = string.Empty;
try
{
result = OpenSysEnvironment().GetValue(name).ToString();//读取
}
catch (Exception)
{
return string.Empty;
}
return result;
}
/// <summary>
/// 打开系统环境变量注册表
/// </summary>
/// <returns>RegistryKey</returns>
private static RegistryKey OpenSysEnvironment()
{
RegistryKey regLocalMachine = Registry.LocalMachine;
RegistryKey regSYSTEM = regLocalMachine.OpenSubKey("SYSTEM", true);//打开HKEY_LOCAL_MACHINE下的SYSTEM
RegistryKey regControlSet001 = regSYSTEM.OpenSubKey("ControlSet001", true);//打开ControlSet001
RegistryKey regControl = regControlSet001.OpenSubKey("Control", true);//打开Control
RegistryKey regManager = regControl.OpenSubKey("Session Manager", true);//打开Control
RegistryKey regEnvironment = regManager.OpenSubKey("Environment", true);
return regEnvironment;
}
/// <summary>
/// 设置系统环境变量
/// </summary>
/// <param name="name">变量名</param>
/// <param name="strValue">值</param>
public static void SetSysEnvironment(string name, string strValue)
{
OpenSysEnvironment().SetValue(name, strValue);
}
/// <summary>
/// 检测系统环境变量是否存在
/// </summary>
/// <param name="name"></param>
/// <returns></returns>
public bool CheckSysEnvironmentExist(string name)
{
if (!string.IsNullOrEmpty(GetSysEnvironmentByName(name)))
return true;
else
return false;
}
/// <summary>
/// 添加到PATH环境变量（会检测路径是否存在，存在就不重复）
/// </summary>
/// <param name="strPath"></param>
public static void SetPathAfter(string strHome)
{
string pathlist ;
pathlist = GetSysEnvironmentByName("PATH");
//检测是否以;结尾
if (pathlist.Substring(pathlist.Length - 1, 1) != ";")
{
SetSysEnvironment("PATH", pathlist + ";");
pathlist = GetSysEnvironmentByName("PATH");
}
string[] list = pathlist.Split(';');
bool isPathExist = false;
foreach (string item in list)
{
if (item == strHome)
isPathExist = true;
}
if (!isPathExist)
{
SetSysEnvironment("PATH", pathlist +strHome+ ";");
}
}
public static void SetPathBefore(string strHome)
{
string pathlist;
pathlist = GetSysEnvironmentByName("PATH");
string[] list = pathlist.Split(';');
bool isPathExist = false;
foreach (string item in list)
{
if (item == strHome)
isPathExist = true;
}
if (!isPathExist)
{
SetSysEnvironment("PATH", strHome + ";" + pathlist);
}
}
public static void SetPath(string strHome)
{
string pathlist;
pathlist = GetSysEnvironmentByName("PATH");
string[] list = pathlist.Split(';');
bool isPathExist = false;
foreach (string item in list)
{
if (item == strHome)
isPathExist = true;
}
if (!isPathExist)
{
SetSysEnvironment("PATH", pathlist + strHome + ";" );
}
}
}
Kernel32.DLL内有SetEnvironmentVariable函数用于设置系统环境变量
C#调用要用DllImport，代码封装如下：
class SetSysEnvironmentVariable
{
[DllImport("Kernel32.DLL ", SetLastError = true)]
public static extern bool SetEnvironmentVariable(string lpName, string lpValue);
public static void SetPath(string pathValue)
{
string pathlist;
pathlist = SysEnvironment.GetSysEnvironmentByName("PATH");
string[] list = pathlist.Split(';');
bool isPathExist = false;
foreach (string item in list)
{
if (item == pathValue)
isPathExist = true;
}
if (!isPathExist)
{
SetEnvironmentVariable("PATH", pathlist + pathValue+";");
}
}
}