Want to protect your cyber security and still get fast solutions? Ask a secure question today.Go Premium

x
  • Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 644
  • Last Modified:

How to get the DWORD registry value on local machine?

Hi, I want to retrieve the DWORD registy value in DWORD type variable. Could anyone tell me how to query directly DWORD value and stored it in DWORD type variable. I know how to retrieve string registry key. See attached code.

Thanks.
HKEY lHKeyhandle;
HKEY lhkey;
LONG lRetVal;
char* mykey;
lRetVal = RegConnectRegistry(NULL, HKEY_LOCAL_MACHINE, &lHKeyhandle);
if(lRetVal == ERROR_SUCCESS) {		
	lRetVal = RegOpenKeyEx(lHKeyhandle, "SOFTWARE\\Microsoft\\Software\\MyApp", 0, KEY_QUERY_VALUE, &lhkey);
	if(lRetVal == ERROR_SUCCESS) {  	
		LPBYTE lpData = new BYTE[_MAX_FNAME + 1];
		ZeroMemory(lpData, _MAX_FNAME + 1);
		DWORD lpcbData = _MAX_FNAME;			
                                          lRetVal = RegQueryValueExA(lhkey, TEXT("MyKey"), NULL, NULL, lpData, &lpcbData);
                                          mykey = new char[_MAX_FNAME];
		if(lRetVal == ERROR_SUCCESS)
		    sprintf(mykey, "%s", lpData);		
		RegCloseKey(lhkey);
	}
	RegCloseKey(lHKeyhandle);
}

Open in new window

0
deshaw
Asked:
deshaw
  • 3
  • 2
3 Solutions
 
evilrixSenior Software Engineer (Avast)Commented:
http://msdn.microsoft.com/en-us/library/ms724868(VS.85).aspx

LONG WINAPI RegGetValue(
  __in         HKEY hkey,
  __in_opt     LPCTSTR lpSubKey,
  __in_opt     LPCTSTR lpValue,
  __in_opt     DWORD dwFlags,
  __out_opt    LPDWORD pdwType,
  __out_opt    PVOID pvData, //<-------------  &dwData
  __inout_opt  LPDWORD pcbData
);

Pass pvData as the address of a DWORD variable
0
 
jkrCommented:
Or, in your code:
HKEY lHKeyhandle;
HKEY lhkey;
LONG lRetVal;
char* mykey;
lRetVal = RegConnectRegistry(NULL, HKEY_LOCAL_MACHINE, &lHKeyhandle);
if(lRetVal == ERROR_SUCCESS) {          
        lRetVal = RegOpenKeyEx(lHKeyhandle, "SOFTWARE\\Microsoft\\Software\\MyApp", 0, KEY_QUERY_VALUE, &lhkey);
        if(lRetVal == ERROR_SUCCESS) {          
                DWORD dwValue;
                
                DWORD lpcbData = sizeof(DWORD);                    
                                          lRetVal = RegQueryValueExA(lhkey, TEXT("MyKey"), NULL, NULL, (LPBYTE) &dwValue, &lpcbData);
                                         
                if(lRetVal == ERROR_SUCCESS)
                    sprintf(mykey, "%d", dwValue);               
                RegCloseKey(lhkey);
        }
        RegCloseKey(lHKeyhandle);
}

Open in new window

0
 
deshawAuthor Commented:
Thanks both of you. The posts were helpful. My solution is below and working fine. Let me know if you think there is any amiss.
HKEY lhkey;
LONG lRetVal;
DWORD dwType, dwSize;
//set default value
DWORD mykey= 0;

try {
     if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, "SOFTWARE\\MyApp", 0, KEY_QUERY_VALUE, &lhkey) == ERROR_SUCCESS) {
    dwType = REG_DWORD;
    dwSize = sizeof(DWORD);
    RegQueryValueEx(lhkey, TEXT("myRegKey"), NULL, &dwType, (PBYTE)&mykey, &dwSize);
    RegCloseKey(lhkey);
    }
} catch(...) {
//ignore and take default value
}
Thanks.
0
Concerto Cloud for Software Providers & ISVs

Can Concerto Cloud Services help you focus on evolving your application offerings, while delivering the best cloud experience to your customers? From DevOps to revenue models and customer support, the answer is yes!

Learn how Concerto can help you.

 
jkrCommented:
You can omit try/catch here, since no C++ exceptions are going to be thrown. SEH might be more appropriate, e.g.
__try {
     if(RegOpenKeyEx(HKEY_LOCAL_MACHINE, "SOFTWARE\\MyApp", 0, KEY_QUERY_VALUE, &lhkey) == ERROR_SUCCESS) {
    dwType = REG_DWORD;
    dwSize = sizeof(DWORD);
    RegQueryValueEx(lhkey, TEXT("myRegKey"), NULL, &dwType, (PBYTE)&mykey, &dwSize);
    RegCloseKey(lhkey);
    }
} __except(1) {
//ignore and take default value
} 

Open in new window

0
 
deshawAuthor Commented:
ohh..great..thanks jkr...
0
 
deshawAuthor Commented:
Thanks...
0

Featured Post

Independent Software Vendors: We Want Your Opinion

We value your feedback.

Take our survey and automatically be enter to win anyone of the following:
Yeti Cooler, Amazon eGift Card, and Movie eGift Card!

  • 3
  • 2
Tackle projects and never again get stuck behind a technical roadblock.
Join Now