專案中遇到需要統計windows平臺硬體資源的需求。採用WMI進行獲取，但在獲取硬碟型號以及對應的邏輯分割槽時被卡住了。 

       我們知道磁碟驅動器與硬碟是一對一的關係，而硬碟與邏輯磁碟是一對多關係。採用WMI中類Win32_DiskDrive能獲取磁碟驅動器資訊，Win32_LogicalDisk能獲取具體邏輯磁碟資訊（包括已使用大小，總大小等）；而GetLogicalDriveStrings 與GetDiskFreeSpaceEx Win32 API能夠獲取與Win32_LogicalDisk相同的資訊。以上無法滿足需求，如何將磁碟驅動器的磁碟型號資訊與邏輯磁碟資訊對應呢？下面直接上程式碼（程式碼是我從MSDN上找的啦~。~，少量改寫）。

#define _WIN32_DCOM
#include <iostream>
using namespace std;
#include <comdef.h>

#include <Wbemidl.h>

#pragma comment(lib, "wbemuuid.lib")

BOOL wmi_run();
BOOL wmi_getDriveLetters();
BOOL wmi_close();

IWbemLocator *pLoc = NULL;
IWbemServices *pSvc = NULL;

int main(int argc, char **argv)
{
	wmi_run();
	wmi_getDriveLetters();

	system("pause");
	wmi_close();
}

//
// Step 1-5 at:
// https://msdn.microsoft.com/en-us/library/aa390423(VS.85).aspx
BOOL wmi_run()
{
	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 need to 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 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
		);



	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 root\cimv2 namespace with
	// the current user and obtain pointer pSvc
	// to make IWbemServices calls.
	hres = pLoc->ConnectServer(
		_bstr_t(L"ROOT\\CIMV2"), // 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
		);

	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 on 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.
	}
	return 0;
}

//
// get Drives, logical Drives and Driveletters
BOOL wmi_getDriveLetters()
{
	// Use the IWbemServices pointer to make requests of WMI. 
	// Make requests here:
	HRESULT hres;
	IEnumWbemClassObject* pEnumerator = NULL;

	// get localdrives
	hres = pSvc->ExecQuery(
		bstr_t("WQL"),
		bstr_t("SELECT * FROM Win32_DiskDrive"),
		WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
		NULL,
		&pEnumerator);

	if (FAILED(hres)) {
		cout << "Query for processes failed. "
			<< "Error code = 0x"
			<< hex << hres << endl;
		pSvc->Release();
		pLoc->Release();
		CoUninitialize();
		return FALSE;               // Program has failed.
	}
	else {

		IWbemClassObject *pclsObj;
		ULONG uReturn = 0;
		while (pEnumerator) {
			hres = pEnumerator->Next(WBEM_INFINITE, 1,
				&pclsObj, &uReturn);
			if (0 == uReturn) break;

			VARIANT vtProp;
			hres = pclsObj->Get(_bstr_t(L"DeviceID"), 0, &vtProp, 0, 0);

			// adjust string
			wstring tmp = vtProp.bstrVal;
			tmp = tmp.substr(4);

			// Size屬性可以獲取硬碟的大小哦（暫時註釋掉啦）
			// 如果需要使用的話，注意先判斷vtProp的型別，目前雖然VARIANT結構體內建多種型別，
			// 但目前只支援四種類型：VT_I4、VT_DISPATCH、VT_BSTR、VT_EMPTY
			// 對應獲取值得名稱：lVal、pdispVal、bstrVal、none
			// 例如：vtProp型別為VT_BSTR，獲取值為vtProp.bstrValue
			// 最後注意：獲取的值為寬字元，可以通過WideCharToMultiByte轉化為多字元
			// pclsObj->Get(L"Size", 0, &vtProp, 0, 0);

			// 列印硬碟型號
			pclsObj->Get(L"Caption", 0, &vtProp, 0, 0);
			if (!(vtProp.vt == VT_EMPTY || vtProp.vt == VT_I4 ||
				vtProp.vt == VT_DISPATCH))
				printf("硬碟型號:%ls\n", vtProp.bstrVal);

			wstring wstrQuery = L"Associators of {Win32_DiskDrive.DeviceID='\\\\.\\";
			wstrQuery += tmp;
			wstrQuery += L"'} where AssocClass=Win32_DiskDriveToDiskPartition";

			// reference drive to partition
			IEnumWbemClassObject* pEnumerator1 = NULL;
			hres = pSvc->ExecQuery(
				bstr_t("WQL"),
				bstr_t(wstrQuery.c_str()),
				WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
				NULL,
				&pEnumerator1);

			if (FAILED(hres)) {
				cout << "Query for processes failed. "
					<< "Error code = 0x"
					<< hex << hres << endl;
				pSvc->Release();
				pLoc->Release();
				CoUninitialize();
				return FALSE;               // Program has failed.
			}
			else {

				IWbemClassObject *pclsObj1;
				ULONG uReturn1 = 0;
				while (pEnumerator1) {
					hres = pEnumerator1->Next(WBEM_INFINITE, 1,
						&pclsObj1, &uReturn1);
					if (0 == uReturn1) break;

					// 此處獲取的都是Win32_DiskPartition磁碟分割槽資訊
					// 我們的需求不會使用到，保持不變即可

					// reference logical drive to partition
					VARIANT vtProp1;
					hres = pclsObj1->Get(_bstr_t(L"DeviceID"), 0, &vtProp1, 0, 0);
					//printf("DeviceID:%ls\n",vtProp1.bstrVal);

					wstring wstrQuery = L"Associators of {Win32_DiskPartition.DeviceID='";
					wstrQuery += vtProp1.bstrVal;
					wstrQuery += L"'} where AssocClass=Win32_LogicalDiskToPartition";

					IEnumWbemClassObject* pEnumerator2 = NULL;
					hres = pSvc->ExecQuery(
						bstr_t("WQL"),
						bstr_t(wstrQuery.c_str()),
						WBEM_FLAG_FORWARD_ONLY | WBEM_FLAG_RETURN_IMMEDIATELY,
						NULL,
						&pEnumerator2);

					if (FAILED(hres)) {
						cout << "Query for processes failed. "
							<< "Error code = 0x"
							<< hex << hres << endl;
						pSvc->Release();
						pLoc->Release();
						CoUninitialize();
						return FALSE;               // Program has failed.
					}
					else {

						// get driveletter
						IWbemClassObject *pclsObj2;
						ULONG uReturn2 = 0;
						while (pEnumerator2) {
							hres = pEnumerator2->Next(WBEM_INFINITE, 1,
								&pclsObj2, &uReturn2);
							if (0 == uReturn2) break;

							// 獲取的是Win32_LogicalDisk的資訊
							// 例如：磁碟C,磁碟D都是同一硬碟的邏輯磁碟
							// 可以在單獨獲取磁碟C、磁碟D的剩餘空間，總空間資訊
							// 下面vtProp.bstrVal為上面獲取的硬碟的型號
							// vtProp2.bstrVal為磁碟的碟符C或D
							// 分別獲取磁碟的總大小和剩餘大小。注意事項和硬碟部分描述一樣
							// pclsObj2->Get(L"Size", 0, &vtProp2, 0, 0);
							// pclsObj2->Get(L"FreeSpace", 0, &vtProp2, 0, 0);

							VARIANT vtProp2;
							hres = pclsObj2->Get(_bstr_t(L"DeviceID"), 0, &vtProp2, 0, 0);
							// print result
							printf("硬碟型號:%ls\t磁碟碟符:%ls\n", vtProp.bstrVal, vtProp2.bstrVal);
							VariantClear(&vtProp2);
						}
						pclsObj1->Release();
					}
					VariantClear(&vtProp1);
					pEnumerator2->Release();
				}
				pclsObj->Release();
			}
			VariantClear(&vtProp);
			pEnumerator1->Release();
		}
	}
	pEnumerator->Release();
	return TRUE;
}






BOOL wmi_close()
{
	// Cleanup
	// ========

	pSvc->Release();
	pLoc->Release();
	CoUninitialize();

	return 0;   // Program successfully completed. 
}
 

執行結果：

我的電腦上只有一塊硬碟，硬碟對應的邏輯磁碟分割槽分別為C、D。到此完成了。