Registry - Check for key or value Hello, I am trying to check for the existance of

[NewPlaza]

Registry - Check for key or value

Hello,

I am trying to check for the existance of a key or value in the registry.
I know how to write the values,

RegSetKeyValue(HKEY_CURRENT_USER, "Software\\Microsoft\\Windows\\CurrentVersion\\Run", "StartupBuddy", REG_SZ, "0", 1);

RegSetKeyValue(HKEY_CURRENT_USER, "Software\\Microsoft\\Windows\\CurrentVersion\\Run", "StartupBuddy", REG_SZ, "1", 1);

CreateWindow(TEXT("BUTTON"),// * GroupBox
 TEXT("Startup Settings"),
 WS_VISIBLE | WS_CHILD | BS_GROUPBOX | BS_CENTER,
 10, // Start Left
 10, // Start Top
 WidthX - 25,
 50,
 hwnd,
 (HMENU) ID_GroupBox_StartupSettings,
 NULL,
 NULL);
					
CreateWindow(TEXT("BUTTON"),// * CheckBox
 TEXT("Start with Windows"),
 WS_VISIBLE | WS_CHILD | BS_CHECKBOX,
 30, // Start Left
 25, // Start Top
 150,
 30,
 hwnd,
 (HMENU) ID_CheckBox_WindowsStartup,
 NULL,
 NULL);

But do not know how to check for them
check for value in registry, if found

CheckDlgButton(hwnd, ID_CheckBox_WindowsStartup, BST_CHECKED);

Thank you.

[VictorN]

Have a loo at RegEnumKey and RegEnumValue functions.

[2kaud]

Also RegGetValue()
https://learn.microsoft.com/en-us/wi...g-reggetvaluea

[NewPlaza]

Thank you for your replies.
2kaud, I actually have tried RegGetValue() but have issues using it. I also tried RegQueryValue() with limited success.

My code for that statement.

char szPath[MAX_PATH];
LONG cbValue=sizeof(szPath);
if(!RegQueryValue(HKEY_CURRENT_USER, "Software\\Microsoft\\Windows\\CurrentVersion\\Run", "StartupBuddy", &cbValue)==ERROR_SUCCESS){
printf( "StartupBuddy key not found. App not set to boot with Windows.\n" );
// Do nothing.....}
else {
printf( "StartupBuddy key found. App is set to boot with Windows.\n" );
CheckDlgButton(hwnd, ID_CheckBox_WindowsStartup, BST_CHECKED);//Check "Start with Windows" checkbox.
}

It works only when the key isn't found in the registry. BUT will crash(exits prematurely or unexpected) when the key already exists.
Thanks.

[VictorN]

My code for that statement.

char szPath[MAX_PATH];
LONG cbValue=sizeof(szPath);
if (!RegQueryValue(HKEY_CURRENT_USER, "Software\\Microsoft\\Windows\\CurrentVersion\\Run", "StartupBuddy", &cbValue)==ERROR_SUCCESS)
{
         printf( "StartupBuddy key not found. App not set to boot with Windows.\n" );
         // Do nothing....
}

Try:

char szPath[MAX_PATH];
LONG cbValue=sizeof(szPath);
LSTATUS errorCode = RegQueryValue(HKEY_CURRENT_USER, "Software\\Microsoft\\Windows\\CurrentVersion\\Run", "StartupBuddy", &cbValue);
if (errorCode != ERROR_SUCCESS)
{
         printf( "StartupBuddy key not found. App not set to boot with Windows.\n" );
         // Do nothing....
}

[2kaud]

You are using RegQueryValue() incorrectly. The first param is the key to be used (already opened), the second is the value to be retrieved, the 3rd the address of where to place the retrieved data and the 4th a pointer to a value that has the maximum number of bytes that can be retrieved. But in this case you want RegGetValue(). Something like (NOT tried):

char szPath[MAX_PATH] = {0};
DWORD cbValue=sizeof(szPath);
if (RegGetValue(HKEY_CURRENT_USER, "Software\\Microsoft\\Windows\\CurrentVersion\\Run", "StartupBuddy", RRF_RT_REG_SZ, NULL, szPath, &cbValue) != ERROR_SUCCESS) {
    printf( "StartupBuddy key not found. App not set to boot with Windows.\n" );
    // Do nothing.....
} else {
    printf( "StartupBuddy key found. App is set to boot with Windows.\n" );
    CheckDlgButton(hwnd, ID_CheckBox_WindowsStartup, BST_CHECKED);    //Check "Start with Windows" checkbox.
}

Note that cbValue is of type DWORD and not LONG.

See https://learn.microsoft.com/en-us/wi...g-reggetvaluea

Note. If you just want to display a string ending with a \n it's easier to use puts()

puts( "StartupBuddy key not found. App not set to boot with Windows." );

[NewPlaza]

2kaud,

Awesome! That worked! Thank you so much!!!