Minecraft启动器制作（C++）

获取Java路径

INT GetJavaHomePathFromRegedit(wchar_t* retwstr) {
	wchar_t str[MAX_PATH + 1];
	INT flag = GetStrFromRegedit(L"SOFTWARE\JavaSoft\Java Runtime Environment\", L"CurrentVersion", str);
	wprintf(L"%wsn", str);

	WCHAR keyjp[MAX_PATH + 1] = L"";
	swprintf_s(keyjp, MAX_PATH, L"%ws%ws", L"SOFTWARE\JavaSoft\Java Runtime Environment\", str);
	wprintf(L"%wsn", keyjp);
	flag = GetStrFromRegedit(keyjp, L"JavaHome", str);
	wprintf(L"%wsn", str);
	swprintf_s(retwstr, MAX_PATH, L"%ws%ws", str, L"\bin\java.exe");
	return TRUE;
}

INT GetStrFromRegedit(const wchar_t* hkey, const wchar_t* childkey, wchar_t* str) {
	HKEY retKey;
	BYTE retKeyVal[MAX_PATH + 1] = { 0 };
	DWORD nSize = MAX_PATH + 1;
	LONG ret = RegOpenKeyEx(HKEY_LOCAL_MACHINE, hkey, 0, KEY_QUERY_VALUE | KEY_READ, &retKey);
	//记得加KEY_READ来读取多级子键
	if (ret != ERROR_SUCCESS) {
		return -1;
	}
	ret = RegQueryValueEx(retKey, childkey, NULL, NULL, (LPBYTE)retKeyVal, &nSize);
	RegCloseKey(retKey);
	if (ret != ERROR_SUCCESS) {
		return -2;
	}
	int sum = 0;
	wchar_t TEMPSTR[MAX_PATH + 1] = L"";
	for (int i = 0; i < int(nSize); i += 1) {
		if (retKeyVal[i + 1] == 0) {
			TEMPSTR[i] = retKeyVal[i];
			if (retKeyVal[i] == 0) break;
		}
	}
	for (int i = 0; i < int(nSize); i += 1) {
		if (retKeyVal[i + 1] == 0) {
			*(str + sum) = retKeyVal[i];
			sum++;
			if (retKeyVal[i] == 0) break;
		}
	}
	return TRUE;
}