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2026-06-18

获取环境变量 - RegistryGetEnvironmentVariable ​

函数简介 ​

获取环境变量的值，支持读取用户级和系统级环境变量。

接口名称 ​

RegistryGetEnvironmentVariable

DLL调用 ​

cpp
int64_t RegistryGetEnvironmentVariable(int64_t instance, const char* name, int32_t systemWide);

参数说明 ​

参数名类型说明
instance长整数型OLAPlug对象的指针，由 CreateCOLAPlugInterFace 接口生成。
name字符串环境变量名称。
systemWide整数型是否从系统级环境变量读取。1 系统级，0 当前用户级。

示例 ​

SDK 调用 ​

cpp
#include "OLAPlugServer.h"

OLAPlugServer ola;
std::string path = ola.RegistryGetEnvironmentVariable("PATH", 0);
csharp
using OLAPlug;

var ola = new OLAPlugServer();
string path = ola.RegistryGetEnvironmentVariable("PATH", 0);
python
from OLAPlugServer import OLAPlugServer

ola = OLAPlugServer()
path = ola.RegistryGetEnvironmentVariable("PATH", 0)
java
import com.olaplug.OLAPlugServer;

OLAPlugServer ola = new OLAPlugServer();
ola.RegistryGetEnvironmentVariable("PATH", 0);
cpp
var ola = com("OlaPlug.OlaSoft")
ola.RegistryGetEnvironmentVariable("PATH", 0);
vbscript
Set ola = CreateObject("OlaPlug.OlaSoft")
ola.RegistryGetEnvironmentVariable("PATH", 0);
text
.局部变量 ola, OLAPlug
ola.创建 ()
ola.RegistryGetEnvironmentVariable("PATH", 0);
aardio
import OLAPlugServer;
var ola = OLAPlugServer();
ola.RegistryGetEnvironmentVariable("PATH", 0);
text
变量 ola <类型 = OLAPlugServer>
ola = 新建 OLAPlugServer
ola.RegistryGetEnvironmentVariable("PATH", 0);
cpp
#include "OLAPlugServer.h"

OLAPlugServer ola;
ola.RegistryGetEnvironmentVariable("PATH", 0);

原生 DLL 调用 ​

cpp
long instance = CreateCOLAPlugInterFace();
long ptr = RegistryGetEnvironmentVariable(instance, "PATH", 0);
if (ptr != 0) {
    char buffer[4096] = {0};
    GetStringFromPtr(ptr, buffer, sizeof(buffer));
    FreeStringPtr(ptr);
}
csharp
using System.Runtime.InteropServices;
using System.Text;

[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern int GetStringFromPtr(long ptr, StringBuilder lpString, int size);
[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern int FreeStringPtr(long ptr);
[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern int GetStringSize(long ptr);
[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern long CreateCOLAPlugInterFace();
[DllImport("OLAPlug_x64.dll", CallingConvention = CallingConvention.StdCall)]
static extern long RegistryGetEnvironmentVariable(long ola, string name, int scope);

long instance = CreateCOLAPlugInterFace();
long ptr = RegistryGetEnvironmentVariable(instance, "PATH", 0);
if (ptr != 0) {
    StringBuilder sb = new StringBuilder(GetStringSize(ptr) + 1);
    GetStringFromPtr(ptr, sb, sb.Capacity);
    FreeStringPtr(ptr);
    string path = sb.ToString();
}
python
from ctypes import CDLL, c_int, c_int64

ola = CDLL("OLAPlug_x64.dll")
ola.CreateCOLAPlugInterFace.restype = c_int64
instance = ola.CreateCOLAPlugInterFace()
ptr = ola.RegistryGetEnvironmentVariable(instance, b"PATH", 0)

返回值 ​

返回值说明
（返回值）长整数型。成功返回环境变量值的字符串指针，失败或不存在返回 0。返回的字符串指针需调用 FreeStringPtr 释放内存。

注意事项 ​

项目说明
环境变量名称不区分大小写环境变量名称不区分大小写。
系统级环境变量存储在 HKEY_LOCAL_MA系统级环境变量存储在 HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment。
用户级环境变量存储在 HKEY_CURRENT_用户级环境变量存储在 HKEY_CURRENT_USER\Environment。