Use of Allocations w/ cbClsExtra & cbWndExtra in Windows

 Last reviewed: November 2, 1995
Article ID: Q11606
The information in this article applies to:
  • Microsoft Windows Software Development Kit (SDK) for Windows versions 3.0 and 3.1
  • Microsoft Win32 Application Programming Interface (API) included with: 

        - Microsoft Windows NT versions 3.5 and 3.51
    - Microsoft Windows 95 version 4.0

The following is an explanation of the use of the allocations with cbClsExtra and cbWndExtra?:

  1. cbClsExtra -- extra bytes to allocate to CLASS data structure in USER.EXE local heap when RegisterClass() is called. Accessed by Get/Set CLASS Word/Long ();.

  2. cbWndExtra -- extra bytes to allocate to WND data structure in USER.EXE local heap when CreateWindow() is called. Accessed by Get/Set WND Word/Long ();.

You can use these structures at your discretion and for any purpose you desire.

Additional reference words: 3.00 3.10 3.50 4.00 95
KBCategory: kbui
KBSubcategory: UsrCls

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Last reviewed: November 2, 1995
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