Home   Index   About
Ultimate Pack


Custom Search
Predefined Keys

An application must open a key before it can add data to the registry. To open a key, an application must supply the handle of another key in the registry that is already open. The system defines standard handles that are always open. An application can use these predefined handles as entry points to the registry.

The system provides two predefined keys at the root of the registry: HKEY_LOCAL_MACHINE and HKEY_USERS. In addition, the system defines two subkeys: HKEY_CLASSES_ROOT (a subkey of HKEY_LOCAL_MACHINE) and HKEY_CURRENT_USER (a subkey of HKEY_USERS). These registry handles are valid for all Win32 implementations of the registry, although the use of the handles may vary from platform to platform.

Predefined keys help an application navigate in the registry and make it possible to develop tools that allow a system administrator to manipulate categories of data. Applications that add data to the registry should always work within the framework of predefined keys, so administrative tools can find and use the new data.

These predefined keys are used as entry points to the registry.

Entry point
Use
HKEY_CLASSES_ROOT
Registry entries subordinate to this key define types (or classes) of documents and the properties associated with those types. Data stored under this key is used by Windows shell applications and by object linking and embedding (OLE) applications.
HKEY_CURRENT_USER
Registry entries subordinate to this key define the preferences of the current user. These preferences include the settings of environment variables, data about program groups, colors, printers, network connections, and application preferences.
HKEY_LOCAL_MACHINE
Registry entries subordinate to this key define the physical state of the computer, including data about the bus type, system memory, and installed hardware and software.
HKEY_USERS
Registry entries subordinate to this key define the default user configuration for new users on the local computer and the user configuration for the current user.

The use of HKEY_CURRENT_USER, HKEY_LOCAL_MACHINE, and HKEY_USERS varies depending on the implementation of the registry. In addition, other predefined handles have been defined for specific Windows platforms.


Last news from Greatis Software

Nostalgia .Net     Nostalgia .Net     .Net is powerful, but not all-powerful, so sometimes we need to use Win32 API for our .Net applications. It's simple enough with Platform Invoke if you have Win32 skill, but we do not always have time to dig the ancient documentation, declare the special types that are compatible with Win32, find the values of the Win32's constants and so on. Nostalgia .Net offers several simple-to-use classes, and components that will allow you to forget about the headache of Win32 and just use the power of Win32 in your application the same way as you use the native. Net classes.  More »

Recommended software for developers

Ultimate Pack for Delphi and C++ Builder     Ultimate Pack     Component pack for Delphi and C++ Builder that contains runtime form designer, runtime object inspector, print suite and much more for the very special price.  More »

Form Designer .Net     Form Designer .Net     Unique runtime form design solution that allows to edit any form in .Net WinForms application at runtime with full source codes for only 300 euro!  More »

Print Suite .Net     Print Suite .Net     Print Suite .Net is a set of components for easy printing texts, images and grids from your WinForms applications. Full C# source codes are available  More »

Gradient Controls .Net     Gradient Controls .Net     Gradient Controls .Net offers controls with gradient background feature. Labels, panels and so on... Full C# source codes are available  More »

iGrid     Greatis iGrid     iGrid plots drawing grid right over your desktop, so you can use it everywhere, with any drawing application without any special plugins for different graphic editors.  More »


All the contacts and projects

Dmitry Vasiliev (just.dmitry)

Related Links

Software for Visual Studio .NET developers
Software for Delphi and C++ Builder developers
Software for Visual Basic 6 developers
Delphi Tips&Tricks
MegaDetailed.NET

More Online Helps

Win32 Programmer's Reference
Win32 Multimedia Programmer's Reference
OLE Programmer's Reference
Microsoft Windows Pen API Programmer's Reference
Microsoft Windows Sockets 2 Reference
Microsoft Windows Telephony API (TAPI) Programmer's Reference
Unix Manual Pages

Free Tech Secrets ;) Copyright © 2008-2012 Free Tech Secrets ;) greatis just4fun network just4fun