INFO: Modifying VTables with AddressOf Is Not Supported

 Last reviewed: April 2, 1997
Article ID: Q166215
The information in this article applies to:
  • Microsoft Visual Basic Control Creation, Learning, Professional, and Enterprise Editions for Windows, version 5.0

SUMMARY

In the March 1997 issue of the Visual Basic Programmer's Journal, an article by Matthew Curland and William Storage was published which featured a technique for simulating the calling of function pointers in Microsoft Visual Basic 5.0.

MORE INFORMATION

As described in the article, the technique requires modification of a class's VTable through the use of the AddressOf operator and the CopyMemory and VirtualProtect Win32 API functions.

Modifying VTables and the technique described in the article are not supported by Microsoft.

Visual Basic Programmer's Journal is published by Fawcette Technical Publications, a publisher independent of Microsoft; we make no warranty, implied or otherwise, regarding this publication's content or reliability.

REFERENCES

Visual Basic Programmer's Journal Fawcette Technical Publications March 1997, Volume 7, No. 3 "Modifying vtables with AddressOf." (pgs 131-133)

Additional query words: Vtables pointer recursive recursion hack sort qsort
compare void overwrite
Keywords : kbpolicy vb5all VBCCE VBKBVBA kbinfo
Version : 5.0
Platform : WINDOWS
Issue type : kbinfo

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Last reviewed: April 2, 1997
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