【发布时间】：2014-03-21 16:03:35
【问题描述】：
我正在尝试使用 C++ 和 WMI 的 WIN32_NetworkAdapter 类启用/禁用我的网络以太网接口。但不幸的是，我没有发现如何调用类的方法。 提前谢谢...
【问题讨论】：
-
嗨！欢迎来到 SO！我有点不清楚你在这里问什么。您可以编辑帖子以明确说明您的问题吗？
标签： c++ visual-c++ network-programming wmi
【发布时间】：2014-03-21 16:03:35
【问题描述】：
要执行 WMI 方法，您必须使用 IWbemServices 类的 ExecMethod 方法。在这种情况下，您必须将网络适配器的索引传递给 Enable/Disble 方法。
顺便说一句，如果您是使用 WMI 和 C++ 的新手，您可以使用 WDCC 工具，它可以帮助您生成代码以从 C++ 访问 WMI。
试试这个示例代码。
#include "stdafx.h"
#define _WIN32_DCOM
#include <iostream>
using namespace std;
#include <comdef.h>
#include <Wbemidl.h>
# pragma comment(lib, "wbemuuid.lib")
//CREDENTIAL structure
//http://msdn.microsoft.com/en-us/library/windows/desktop/aa374788%28v=vs.85%29.aspx
#define CRED_MAX_USERNAME_LENGTH 513
#define CRED_MAX_CREDENTIAL_BLOB_SIZE 512
#define CREDUI_MAX_USERNAME_LENGTH CRED_MAX_USERNAME_LENGTH
#define CREDUI_MAX_PASSWORD_LENGTH (CRED_MAX_CREDENTIAL_BLOB_SIZE / 2)
#pragma argsused
int main(int argc, char* argv[])
{
wchar_t pszName[CREDUI_MAX_USERNAME_LENGTH+1] = L"user";
wchar_t pszPwd[CREDUI_MAX_PASSWORD_LENGTH+1] = L"password";
BSTR strNetworkResource;
//To use a WMI remote connection set localconn to false and configure the values of the pszName, pszPwd and the name of the remote machine in strNetworkResource
bool localconn = true;
strNetworkResource = localconn ? L"\\\\.\\root\\CIMV2" : L"\\\\remote--machine\\root\\CIMV2";
COAUTHIDENTITY *userAcct = NULL ;
COAUTHIDENTITY authIdent;
HRESULT hres;
// Initialize COM. ------------------------------------------
hres = CoInitializeEx(0, COINIT_MULTITHREADED);
if (FAILED(hres))
{
cout << "Failed to initialize COM library. Error code = 0x" << hex << hres << endl;
cout << _com_error(hres).ErrorMessage() << endl;
cout << "press enter to exit" << endl;
cin.get();
return 1; // Program has failed.
}
// Set general COM security levels --------------------------
if (localconn)
hres = CoInitializeSecurity(
NULL,
-1, // COM authentication
NULL, // Authentication services
NULL, // Reserved
RPC_C_AUTHN_LEVEL_DEFAULT, // Default authentication
RPC_C_IMP_LEVEL_IMPERSONATE, // Default Impersonation
NULL, // Authentication info
EOAC_NONE, // Additional capabilities
NULL // Reserved
);
else
hres = CoInitializeSecurity(
NULL,
-1, // COM authentication
NULL, // Authentication services
NULL, // Reserved
RPC_C_AUTHN_LEVEL_DEFAULT, // Default authentication
RPC_C_IMP_LEVEL_IDENTIFY, // Default Impersonation
NULL, // Authentication info
EOAC_NONE, // Additional capabilities
NULL // Reserved
);
if (FAILED(hres))
{
cout << "Failed to initialize security. Error code = 0x" << hex << hres << endl;
cout << _com_error(hres).ErrorMessage() << endl;
CoUninitialize();
cout << "press enter to exit" << endl;
cin.get();
return 1; // Program has failed.
}
// Obtain the initial locator to WMI -------------------------
IWbemLocator *pLoc = NULL;
hres = CoCreateInstance(CLSID_WbemLocator, 0, CLSCTX_INPROC_SERVER, IID_IWbemLocator, (LPVOID *) &pLoc);
if (FAILED(hres))
{
cout << "Failed to create IWbemLocator object. " << "Err code = 0x" << hex << hres << endl;
cout << _com_error(hres).ErrorMessage() << endl;
CoUninitialize();
cout << "press enter to exit" << endl;
cin.get();
return 1; // Program has failed.
}
// Connect to WMI through the IWbemLocator::ConnectServer method
IWbemServices *pSvc = NULL;
// Connect to the root\\CIMV2 namespace
// and obtain pointer pSvc to make IWbemServices calls.
if (localconn)
hres = pLoc->ConnectServer(
_bstr_t(strNetworkResource), // Object path of WMI namespace
NULL, // User name. NULL = current user
NULL, // User password. NULL = current
0, // Locale. NULL indicates current
NULL, // Security flags.
0, // Authority (e.g. Kerberos)
0, // Context object
&pSvc // pointer to IWbemServices proxy
);
else
hres = pLoc->ConnectServer(
_bstr_t(strNetworkResource), // Object path of WMI namespace
_bstr_t(pszName), // User name
_bstr_t(pszPwd), // User password
NULL, // Locale
NULL, // Security flags
NULL, // Authority
NULL, // Context object
&pSvc // IWbemServices proxy
);
if (FAILED(hres))
{
cout << "Could not connect. Error code = 0x" << hex << hres << endl;
cout << _com_error(hres).ErrorMessage() << endl;
pLoc->Release();
CoUninitialize();
cout << "press enter to exit" << endl;
cin.get();
return 1; // Program has failed.
}
cout << "Connected to root\\CIMV2 WMI namespace" << endl;
// Set security levels on the proxy -------------------------
if (localconn)
hres = CoSetProxyBlanket(
pSvc, // Indicates the proxy to set
RPC_C_AUTHN_WINNT, // RPC_C_AUTHN_xxx
RPC_C_AUTHZ_NONE, // RPC_C_AUTHZ_xxx
NULL, // Server principal name
RPC_C_AUTHN_LEVEL_CALL, // RPC_C_AUTHN_LEVEL_xxx
RPC_C_IMP_LEVEL_IMPERSONATE, // RPC_C_IMP_LEVEL_xxx
NULL, // client identity
EOAC_NONE // proxy capabilities
);
else
{
// Create COAUTHIDENTITY that can be used for setting security on proxy
memset(&authIdent, 0, sizeof(COAUTHIDENTITY));
authIdent.PasswordLength = wcslen (pszPwd);
authIdent.Password = (USHORT*)pszPwd;
authIdent.User = (USHORT*)pszName;
authIdent.UserLength = wcslen(pszName);
authIdent.Domain = 0;
authIdent.DomainLength = 0;
authIdent.Flags = SEC_WINNT_AUTH_IDENTITY_UNICODE;
userAcct = &authIdent;
hres = CoSetProxyBlanket(
pSvc, // Indicates the proxy to set
RPC_C_AUTHN_DEFAULT, // RPC_C_AUTHN_xxx
RPC_C_AUTHZ_DEFAULT, // RPC_C_AUTHZ_xxx
COLE_DEFAULT_PRINCIPAL, // Server principal name
RPC_C_AUTHN_LEVEL_PKT_PRIVACY, // RPC_C_AUTHN_LEVEL_xxx
RPC_C_IMP_LEVEL_IMPERSONATE, // RPC_C_IMP_LEVEL_xxx
userAcct, // client identity
EOAC_NONE // proxy capabilities
);
}
if (FAILED(hres))
{
cout << "Could not set proxy blanket. Error code = 0x" << hex << hres << endl;
cout << _com_error(hres).ErrorMessage() << endl;
pSvc->Release();
pLoc->Release();
CoUninitialize();
cout << "press enter to exit" << endl;
cin.get();
return 1; // Program has failed.
}
// Use the IWbemServices pointer to make requests of WMI ----
BSTR MethodName = SysAllocString(L"Disable");
BSTR ClassName = SysAllocString(L"Win32_NetworkAdapter");
IWbemClassObject* pClass = NULL;
hres = pSvc->GetObject(ClassName, 0, NULL, &pClass, NULL);
IWbemClassObject* pInParamsDefinition = NULL;
hres = pClass->GetMethod(MethodName, 0, &pInParamsDefinition, NULL);
IWbemClassObject* pClassInstance = NULL;
hres = pInParamsDefinition->SpawnInstance(0, &pClassInstance);
// Execute Method
IWbemClassObject* pOutParams = NULL;
hres = pSvc->ExecMethod(L"Win32_NetworkAdapter.DeviceID=\"0\"", MethodName, 0,
NULL, pClassInstance, &pOutParams, NULL);
if (FAILED(hres))
{
cout << "Could not execute method. Error code = 0x" << hex << hres << endl;
cout << _com_error(hres).ErrorMessage() << endl;
SysFreeString(ClassName);
SysFreeString(MethodName);
if (pClass) pClass->Release();
if (pInParamsDefinition) pInParamsDefinition->Release();
if (pOutParams) pOutParams->Release();
if (pSvc) pSvc->Release();
if (pLoc) pLoc->Release();
CoUninitialize();
cout << "press enter to exit" << endl;
cin.get();
return 1; // Program has failed.
}
VARIANT varReturnValue;
hres = pOutParams->Get(L"ReturnValue", 0, &varReturnValue, NULL, 0);
if (!FAILED(hres))
wcout << "ReturnValue " << varReturnValue.intVal << endl;
VariantClear(&varReturnValue);
// Clean up
SysFreeString(ClassName);
SysFreeString(MethodName);
if (pClass) pClass->Release();
if (pInParamsDefinition) pInParamsDefinition->Release();
if (pOutParams) pOutParams->Release();
if (pLoc) pLoc->Release();
if (pSvc) pSvc->Release();
CoUninitialize();
cout << "press enter to exit" << endl;
cin.get();
return 0;
}
【讨论】：
-
我尝试执行此代码，但它在运行时生成异常，通过调试指令引发的异常：
hres = pInParamsDefinition->SpawnInstance(0, &pClassInstance); -
能否附上您收到的错误信息？
-
错误是 Exception non gérée à 0x004018d3 dans NetworkToto.exe : 0xC0000005: Violation d'accès lors de la Lecture de l'emplacement 0x00000000。 其中 NetworkToto.exe 是应用程序的名称。我认为这个错误是由于对象
pInParamsDefinition为NULL。 -
如果该变量为 NULL 则
hres = pClass->GetMethod(MethodName, 0, &pInParamsDefinition, NULL);行中存在错误，因此请检查该行之后的hres的值。 -
hres的值是-2147217406。该错误的根源可能是什么？
RRUZ 发布的代码无法按原样工作，因为WIN32_NetworkAdapter 的Disable()（和Enable()）方法没有输入参数。在对ExecMethod() 的调用中，您需要传入一个空值来代替pClassInstance（显然，不要在空值pInParamsDefinition 上调用SpawnInstance()）。但是请注意，这并不一定适用于似乎没有输入参数的所有情况。参见http://microsoft.public.win32.programmer.wmi.narkive.com/Pxy4mfTi/calling-method-with-no-input-params-in-c的讨论
【讨论】：