原文地址:http://stackoverflow.com/questions/4029494/how-to-call-wmi-function-correctly#define _WIN32_DCOM#include <iostream>using namespace std;#include <comdef.h>#include <Wbemidl.h># pragma comment(lib, "wbemuuid.lib")int main(int iArgCnt, char ** argv){ HRESULT hres; // Step 1: -------------------------------------------------- // Initialize COM. ------------------------------------------ hres = CoInitializeEx(0, COINIT_MULTITHREADED); if (FAILED(hres)) { cout << "Failed to initialize COM library. Error code = 0x" << hex << hres << endl; return 1; // Program has failed. } // Step 2: -------------------------------------------------- // Set general COM security levels -------------------------- // Note: If you are using Windows 2000, you must specify - // the default authentication credentials for a user by using // a SOLE_AUTHENTICATION_LIST structure in the pAuthList ---- // parameter of CoInitializeSecurity ------------------------ hres = CoInitializeSecurity( NULL, -1, // COM negotiates service 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 ); if (FAILED(hres)) { cout << "Failed to initialize security. Error code = 0x" << hex << hres << endl; CoUninitialize(); return 1; // Program has failed. } // Step 3: --------------------------------------------------- // 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; CoUninitialize(); return 1; // Program has failed. } // Step 4: --------------------------------------------------- // Connect to WMI through the IWbemLocator::ConnectServer method IWbemServices *pSvc = NULL; // Connect to the local root\cimv2 namespace // and obtain pointer pSvc to make IWbemServices calls. hres = pLoc->ConnectServer( _bstr_t(L"ROOT\\wmi"), NULL, NULL, 0, NULL, 0, 0, &pSvc ); if (FAILED(hres)) { cout << "Could not connect. Error code = 0x" << hex << hres << endl; pLoc->Release(); CoUninitialize(); return 1; // Program has failed. } cout << "Connected to ROOT\\CIMV2 WMI namespace" << endl; // Step 5: -------------------------------------------------- // Set security levels for the proxy ------------------------ 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 ); if (FAILED(hres)) { cout << "Could not set proxy blanket. Error code = 0x" << hex << hres << endl; pSvc->Release(); pLoc->Release(); CoUninitialize(); return 1; // Program has failed. } /////////////////////////////////////////////////////////////////////////////////////////////////////////////// // set up to call the WmiSetBrightness Method BSTR MethodName = SysAllocString(L"WmiSetBrightness"); BSTR ClassName = SysAllocString(L"WmiMonitorBrightnessMethods"); 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); VARIANT var1; VariantInit(&var1); V_VT(&var1) = VT_BSTR; V_BSTR(&var1) = SysAllocString(L"1000"); hres = pClassInstance->Put(L"Timeout", 0, &var1, CIM_UINT32); //CIM_UINT64 VARIANT var2; VariantInit(&var2); V_VT(&var2) = VT_BSTR; V_BSTR(&var2) = SysAllocString(L"30"); hres = pClassInstance->Put(L"Brightness", 0, &var2, CIM_UINT8); // Execute Method IWbemClassObject* pOutParams = NULL; hres = pSvc->ExecMethod(ClassName, MethodName, 0, NULL, pClassInstance, &pOutParams, NULL); if (FAILED(hres)) { cout << "Could not execute method. Error code = 0x" << hex << hres << endl; //VariantClear(&varCommand); SysFreeString(ClassName); SysFreeString(MethodName); pClass->Release(); pInParamsDefinition->Release(); pOutParams->Release(); pSvc->Release(); pLoc->Release(); CoUninitialize(); return 1; // Program has failed. } // To see what the method returned, // use the following code. The return value will // be in &varReturnValue VARIANT varReturnValue; hres = pOutParams->Get(_bstr_t(L"ReturnValue"), 0, &varReturnValue, NULL, 0); // Clean up //-------------------------- // VariantClear(&varCommand); VariantClear(&varReturnValue); SysFreeString(ClassName); SysFreeString(MethodName); pClass->Release(); pInParamsDefinition->Release(); pOutParams->Release(); pLoc->Release(); pSvc->Release(); CoUninitialize(); return 0;}
