Setting A Reg Key Problem

Question

0.00/5 (No votes)

See more:

I'm trying set a regkey 1803 to 3 and am having some problems....these are the values.
Value Name: 1803
Data Type: REG_DWORD (DWORD Value)
Value Data: (0 = downloads enabled, 3 = downloads disabled)

Here is my code...

C++

#include "stdafx.h"
#include <windows.h>
#include <winreg.h>

#pragma comment(lib,"Advapi32.lib")
//#pragma (dll,Advapi32.dll) What To Do ??????????? 
int main () {
	HKEY hKey;			
	DWORD buffersize = 1024;
	char* lpData = new char[buffersize];

	RegOpenKeyEx (HKEY_CURRENT_USER,L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\\Zones\\3",NULL,KEY_SET_VALUE,&hKey);
	RegQueryValueEx(hKey,L"1803",NULL,REG_DWORD,(LPBYTE) lpData,&buffersize);
	RegSetValueExW(hKey,L"1803",REG_DWORD,(LPBYTE) lpData,,3);
	RegCloseKey (hKey);
	delete lpData;
}

Here are my errors...
1 IntelliSense: argument of type "int" is incompatible with parameter of type "LPDWORD"
2 IntelliSense: argument of type "LPBYTE" is incompatible with parameter of type "DWORD"
3 IntelliSense: expected an expression

Posted 11-Sep-11 9:06am

Member 7766180

Updated 11-Sep-11 20:43pm

Emilio Garavaglia

v2

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

**`Randor`** · Accepted Answer · 2011-09-11T11:38:00

Solution 2

Hi,

Many things are wrong with the original code you posted.

1.) You should check the return value of RegOpenKeyEx for ERROR_SUCCESS.
2.) You are trying to read the registry value... but you open the key with only KEY_SET_VALUE.
3.) You are allocating a dynamic array when your obviously using a constant buffer size.
4.) Some missing function parameters.
5.) You should use the correct delete[] operator.

Something like this should work:

C++

#define BUFFER_SIZE 1024 //add this to your header		
HKEY hKey;			
DWORD dwErr = NO_ERROR;

dwErr = RegOpenKeyEx (HKEY_CURRENT_USER,L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\\Zones\\3",NULL,KEY_SET_VALUE|KEY_QUERY_VALUE,&hKey);
if(ERROR_SUCCESS == dwErr)
{
	BYTE data[BUFFER_SIZE] = {0};
	DWORD dwType = REG_NONE;

	dwErr = RegQueryValueEx(hKey,L"1803",NULL,&dwType,data,&buffersize);
	if(ERROR_SUCCESS == dwErr && REG_DWORD == dwType)
	{
		*((LPDWORD)data) = 0;
		dwErr = RegSetValueExW(hKey,L"1803",0,REG_DWORD,data,sizeof(DWORD));
	}
	RegCloseKey (hKey);
}

Also... if you are on a 64 bit operating system and writing a 32 bit application you will need to add KEY_WOW64_64KEY to your RegOpenKeyEx flags.

Best Wishes,
-David Delaune

Posted 11-Sep-11 11:38am

Randor

Updated 11-Sep-11 13:14pm

v4

Comments

Member 7766180 11-Sep-11 18:29pm

Thank you for the information, I guess I did a lot wrong!!! I put this together and I'm getting this error on dwErr. (No storage class or type specifier) Also where does it set the value to 3, I don't see it.

#include "stdafx.h"
#include <windows.h>
#include <winreg.h>
#pragma comment(lib,"Advapi32.lib")

int _main(){
HKEY hKey;
DWORD buffersize = 1024;
DWORD dwErr = NO_ERROR;

dwErr = RegOpenKeyEx (HKEY_CURRENT_USER,L"Software\\Microsoft\\Windows\\CurrentVersion\\Internet Settings\\Zones\\3",NULL,KEY_SET_VALUE|KEY_QUERY_VALUE,&hKey);
if(ERROR_SUCCESS == dwErr)
{
BYTE data[BUFFER_SIZE] = {0};
DWORD dwType = REG_NONE;

dwErr = RegQueryValueEx(hKey,L"1803",NULL,&dwType,data,&buffersize);
if(ERROR_SUCCESS == dwErr && REG_DWORD == dwType)
{
*((LPDWORD)data) = 0;
dwErr = RegSetValueExW(hKey,L"1803",0,REG_DWORD,data,sizeof(DWORD));
}
RegCloseKey (hKey);
}

[no name] 11-Sep-11 19:07pm

If your getting an error "No storage class or type specifier" then that would imply that you are missing a type definition. Make sure you are #including windows.h which will pull in the windef.h header. Also make sure you #define BUFFER_SIZE

The value that is written into the registry is here:

*((LPDWORD)data) = 0;

It essentially casts the pointer from the BYTE array into a pointer to a DWORD and then sets the value to zero.

Best Wishes,
-David Delaune

Member 7766180 11-Sep-11 19:23pm

Thank you, found the problem a "{" was missing! Now this shows up!
Warning 1 warning C4739: reference to variable 'data' exceeds its storage space
Error 2 error LNK2019: unresolved external symbol _main referenced in function ___tmainCRTStartup
Error 3 error LNK1120: 1 unresolved externals

[no name] 11-Sep-11 19:29pm

Sounds like you need to add: #define BUFFER_SIZE 1024

Member 7766180 11-Sep-11 19:30pm

Thanks I saw that.

Member 7766180 11-Sep-11 19:33pm

Yessssssssss! It works! Thank you so much!

Sergey Alexandrovich Kryukov 11-Sep-11 22:57pm

Good points and effective help.
--SA