Windows Program Resources Overview

Windows Program Resources

• Windows program resources are binary data embedded in executable modules.
• Standard resource types include: cursors, bitmaps, icons, menus, dialog boxes, string tables, message tables, fonts, accelerator tables, version information, Plug and Play resources, VXD resources, HTML resources, manifest files, and RCData (raw binary data).
• Dialog boxes are loaded from resources and executed by a single function in single-threaded applications.
• Programmers can create custom resource types.
• Resources are separate from code and data and can be shared across multiple programs.
• Resources can be identified by a number (0 to 65536) or a string within a .exe file.
• Resources are defined using a resource description language (RC language) in .rc files. These are compiled into the .exe file.

Resource Management Functions

• Updating resources:
  • BeginUpdateResource(LPCTSTR pFileName, bool bDeleteExistingResources): Starts resource update process; returns a handle to use in subsequent operations. bDeleteExistingResources specifies whether existing resources should be removed before updating.
  • UpdateResource(HANDLE hUpdate, LPCTSTR lpType, LPCTSTR lpName, WORD wLanguage, void* lpData, DWORD cbData): Adds, removes, or replaces a resource. Called multiple times between BeginUpdateResource and EndUpdateResource.
  • EndUpdateResource(HANDLE hUpdate, bool fDiscard): Finishes resource updating; if fDiscard is true, resource updates are cancelled.

Loading Resources

• Locating resources:
  • FindResourceEx(HMODULE hModule, LPCTSTR lpType, LPCTSTR lpName, WORD wLanguage): Locates a resource with given type, name, and language in a specified module. Related functions include FindResource.
• Loading resources into memory:
  • LoadResource(HMODULE hModule, HRSRC hResInfo): Loads specified resource into global memory; related loading functions include LoadImage, LoadMenu, etc.
• Getting resource size:
  • SizeofResource(HMODULE hModule, HRSRC hResInfo): Gets the size of a loaded resource in memory.