c++ - 我无法使用 RegOpenKeyEx

Question

我在读取注册表时遇到问题。此函数查找注册表路径中的条目数。效果很好，我已经测试过了:

void findNumberEntries(registryTest &INSTALLKEY) {

char buffer[50];
char size = sizeof(buffer);
int index = 0;

if(RegOpenKeyEx(INSTALLKEY.hKey,(LPTSTR)(INSTALLKEY.regpath.c_str()),0,KEY_ALL_ACCESS,&INSTALLKEY.hKey) == ERROR_SUCCESS) {     

    DWORD readEntry;

    do {
        readEntry = RegEnumValue(INSTALLKEY.hKey,index,(LPTSTR)buffer,(LPDWORD)&size,NULL,NULL,NULL,NULL);
        index++;
    }
    while(readEntry != ERROR_NO_MORE_ITEMS);
}
INSTALLKEY.number = index;
RegCloseKey(INSTALLKEY.hKey);
}

现在，主要功能:

std::string regpath32 = "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run\\";
struct registryTest {
HKEY hKey;
std::string regpath;
int number;
};

registryTest INSTALLKEY = {HKEY_LOCAL_MACHINE, regpath32};
findNumberEntries(INSTALLKEY);
printf("%d\n",INSTALLKEY.number);
system("PAUSE");
//until here everything works as it should

HKEY hKey = INSTALLKEY.hKey;
std::string regpath = INSTALLKEY.regpath;
char buffer[50];
char size = sizeof(buffer);
std::string bufferString;
DWORD regOpen = RegOpenKeyEx(INSTALLKEY.hKey,(LPTSTR)INSTALLKEY.regpath.c_str(),0,KEY_READ,&INSTALLKEY.hKey);
if(regOpen == ERROR_SUCCESS) //this is the part that fails.
{
    printf("Registry Key was successfully opened\n");
}
else
{
    printf("Unable to open registry key\n");
    LPVOID message; 
    FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
        NULL, GetLastError(), NULL,(LPTSTR) &message, 0, NULL );
    MessageBox(NULL,(LPCTSTR)message,"ERROR",MB_OK|MB_ICONINFORMATION);
}

...rest of the code

我总是收到“无法打开注册表”并且收到的错误消息是“没有更多文件”。什么问题？？

Answer 1

你的问题是，当你第一次打开注册表项时，你将它分配给了结构的 hkey-member。所以第二次这个 hkey 不再包含原来的 basekey。

改变:

DWORD regOpen = RegOpenKeyEx(INSTALLKEY.hKey,(LPTSTR)INSTALLKEY.regpath.c_str(),0,KEY_READ,&INSTALLKEY.hKey);

进入

DWORD regOpen = RegOpenKeyEx( HKEY_LOCAL_MACHINE ,(LPTSTR)INSTALLKEY.regpath.c_str(),0,KEY_READ,&INSTALLKEY.hKey);

或者改变这个:

void findNumberEntries( registryTest &INSTALLKEY)   
{
  char buffer[50];
  char size = sizeof(buffer); 
  int index = 0; 
  HKEY hkOpen = 0; // can't use INVALID_HANDLE_VALUE for HKEY's;

  if (RegOpenKeyEx( INSTALLKEY.hKey ,(LPTSTR)(INSTALLKEY.regpath.c_str())
                   ,0,&hkOpen ) == ERROR_SUCCESS) 
  {
      // You should use RegQueryInfoKey for below code !
      DWORD readEntry;      
      do {
         readEntry = RegEnumValue( hkOpen ,index,(LPTSTR)buffer
                       ,(LPDWORD size,NULL,NULL,NULL,NULL);
         index++;
     }
    while(readEntry != ERROR_NO_MORE_ITEMS); }
    INSTALLKEY.number = index;
    RegCloseKey( hkOpen );
 }