C++读写注册表、获取子项

//读注册表

std::wstring GetRegValue(HKEY hKeyType, DWORD dwType, LPCTSTR lpPath, LPCTSTR lpName)
{
	HKEY hKEY;
	DWORD dataSize = MAX_PATH;
	char data[MAX_PATH];
	std::string strValue("");
	if (RegOpenKeyEx(hKeyType, lpPath, NULL, KEY_READ, &hKEY) == ERROR_SUCCESS)        //如果无法打开hKEY,则中止程序的执行  
	{
		long lRet = RegQueryValueEx(hKEY, lpName, NULL, &dwType, (LPBYTE)data, &dataSize);
		if (lRet == ERROR_SUCCESS)
		{
			for (int i = 0; i < (int)dataSize; i++)
			{
				strValue = strValue + data[i];
			}
		}
		RegCloseKey(hKEY);        // 程序结束前要关闭已经打开的 hKEY。
	}
	else
	{
		RegCreateKeyEx(hKeyType, (LPCTSTR)lpPath, 0, NULL, NULL, KEY_WRITE, NULL, &hKEY, NULL);
		RegCloseKey(hKEY);        // 程序结束前要关闭已经打开的 hKEY。
	}
	std::wstring wstrValue((wchar_t*)strValue.data(), strValue.length() / 2);
	return wstrValue;
}
eg:
std::wstring strValue;				
strValue = GetRegValue(HKEY_LOCAL_MACHINE, REG_SZ, L"SoftWare\\Microsoft\\Windows\\CurrentVersion\\App Paths\\WebService", L"WebServiceIP");

//写注册表

void WriteRegedit(LPCTSTR m_path, LPCTSTR m_name, CString strParame)
{
	HKEY hKEY;
	if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, m_path, NULL, KEY_WRITE, &hKEY) == ERROR_SUCCESS)        //如果无法打开hKEY,则中止程序的执行  
	{
		RegSetValueEx(hKEY, m_name, NULL, REG_SZ, (BYTE*)strParame.GetBuffer(strParame.GetLength()), 2 * strParame.GetLength());
		strParame.ReleaseBuffer();
		RegCloseKey(hKEY);
	}
	else
	{
		RegCreateKeyEx(HKEY_LOCAL_MACHINE, (LPCTSTR)m_path, 0, NULL, NULL, KEY_WRITE, NULL, &hKEY, NULL);
		RegSetValueEx(hKEY, m_name, NULL, REG_SZ, (BYTE*)strParame.GetBuffer(strParame.GetLength()), 2 * strParame.GetLength());
		strParame.ReleaseBuffer();
		RegCloseKey(hKEY);
	}
}
eg:
m_RegInfo.WriteRegedit(_T("SoftWare\\Microsoft\\Windows\\CurrentVersion\\App Paths\\WebService"), _T("WebServiceIP"), _T("192.168.0.0"));

//获取注册表子项的代码
以下部分内容转自：
http://blog.youkuaiyun.com/helonsy/article/details/7007873

//QueryKey - Enumerates the subkeys of key and its associated values.
//hKey - Key whose subkeys and values are to be enumerated.
#include <windows.h>
#include <stdio.h>
#include <tchar.h>
#define MAX_KEY_LENGTH 255
#define MAX_VALUE_NAME 16383
//枚举一个键的子键和子键的值
void QueryKey(HKEY hKey)
{
	TCHAR    achKey[MAX_KEY_LENGTH];   // buffer for subkey name
	DWORD    cbName;                   // size of name string 
	TCHAR    achClass[MAX_PATH] = TEXT("");  // buffer for class name 
	DWORD    cchClassName = MAX_PATH;  // size of class string 
	DWORD    cSubKeys = 0;               // number of subkeys 
	DWORD    cbMaxSubKey;              // longest subkey size 
	DWORD    cchMaxClass;              // longest class string 
	DWORD    cValues;              // number of values for key 
	DWORD    cchMaxValue;          // longest value name 
	DWORD    cbMaxValueData;       // longest value data 
	DWORD    cbSecurityDescriptor; // size of security descriptor 
	FILETIME ftLastWriteTime;      // last write time 

	DWORD i, retCode;

	TCHAR  achValue[MAX_VALUE_NAME];
	DWORD cchValue = MAX_VALUE_NAME;

	// Get the class name and the value count. 
	retCode = RegQueryInfoKey(
		hKey,                    // key handle 
		achClass,                // buffer for class name 
		&cchClassName,           // size of class string 
		NULL,                    // reserved 
		&cSubKeys,               // number of subkeys 
		&cbMaxSubKey,            // longest subkey size 
		&cchMaxClass,            // longest class string 
		&cValues,                // number of values for this key 
		&cchMaxValue,            // longest value name 
		&cbMaxValueData,         // longest value data 
		&cbSecurityDescriptor,   // security descriptor 
		&ftLastWriteTime);       // last write time 

	// Enumerate the subkeys, until RegEnumKeyEx fails.
	//枚举子项
	if (cSubKeys)
	{
		//printf("\nNumber of subkeys: %d\n", cSubKeys);
		for (i = 0; i < cSubKeys; i++)
		{
			cbName = MAX_KEY_LENGTH;
			retCode = RegEnumKeyEx(hKey, i,
				achKey,
				&cbName,
				NULL,
				NULL,
				NULL,
				&ftLastWriteTime);
			if (retCode == ERROR_SUCCESS)
			{
				_tprintf(TEXT("(%d) %s\n"), i + 1, achKey);//achKey子项的名称			
			}
		}
	}
	
	// Enumerate the key values.
	// 枚举键值
	if (cValues)
	{
		printf("\nNumber of values: %d\n", cValues);
		for (i = 0, retCode = ERROR_SUCCESS; i < cValues; i++)
		{
			cchValue = MAX_VALUE_NAME;
			achValue[0] = '\0';
			retCode = RegEnumValue(hKey, i,
				achValue,
				&cchValue,
				NULL,
				NULL,
				NULL,
				NULL);

			if (retCode == ERROR_SUCCESS)
			{
				_tprintf(TEXT("(%d) %s\n"), i + 1, achValue);
			}
		}
	}
}

//调用部分

void main()
{
	HKEY hTestKey;
	if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, TEXT("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\App Paths"),
		0, KEY_READ, &hTestKey) == ERROR_SUCCESS)
	{
		QueryKey(hTestKey, vecSubkeyName);
	}
	RegCloseKey(hTestKey);
}