Using Win32 functions in Visual FoxPro Image Gallery
Code examples:
How to delete a service object
Retrieving country-specific dialing information from the Windows Telephony list of countries
Closing Windows
GDI+: converting text strings to images and saving in a graphics file
Reading STARTUPINFO structure for the current VFP session
Retrieving default spooling directory name
Saying "Hello World!" with VFP and WinAPI
Validating URLs using moniker functions
How to play a waveform sound (a WAV file in particular)
Copying files as a transacted operation (Vista)
CryptoAPI: retrieving list of providers
GDI+: loading image file, drawing on it, saving the result to another file
Generating random UUID values
Accessing a CD device (cdaudio) with Multimedia Command Strings
Converting long file names to the short format and vice versa
Current directory of the application
GDI+: converting image file to another graphics format
Pocket PC: System Registry Viewer
Retrieving a handle to DLL and address of an exported function in it
WAV file recorder
How to access a file using not its name but an alias (hard link)
Converting a decimal string to an integer
Displaying the color palette stored in an image file
How to perform Base64 encoding/decoding using Cryptography API Functions
Validating the heap of the calling process

User rating: 0/10 (0 votes)
Rate this code sample:
  • ~
More code examples    Listed functions    Add comment     W32 Constants      Translate this page Printer friendly version of this code sample
DO decl


* MSDN: the HEAP_NO_SERIALIZE value can, be safely used 
* the process has only one thread -- this is how the VFP is

LOCAL hProcHeap, lnFreeSize

* retrieving a handle to the heap of the calling process
hProcHeap = GetProcessHeap()
? "Calling process heap handle:", hProcHeap

* making an attempt to compact the calling process heap
* supported in Windows NT/2000/XP, not in Windows 95/98/Me
lnFreeSize = HeapCompact (hProcHeap, HEAP_NO_SERIALIZE)
IF lnFreeSize = 0
* 120 = This function is not supported on this system.
    ? "Error code:", GetLastError()
    ? "The largest committed free block in the heap:",;
            ALLTRIM(TRANS(lnFreeSize, "999,999,999,999,999")), "bytes"

* validating the calling process heap
? "The heap is valid:",;
    Iif(HeapValidate (hProcHeap, HEAP_NO_SERIALIZE, 0)=0, "No","Yes")

    DECLARE INTEGER GetLastError IN kernel32
    DECLARE INTEGER GetProcessHeap IN kernel32

    DECLARE INTEGER HeapCompact IN kernel32;
        INTEGER hHeap, INTEGER dwFlags

    DECLARE INTEGER HeapValidate IN kernel32;
        INTEGER hHeap, INTEGER dwFlags, INTEGER lpMem

User rating: 0/10 (0 votes)
Rate this code sample:
  • ~
1189 bytes  
Created: 2001-12-01 08:43:07  
Modified: 2001-12-01 08:43:41  
Visits in 7 days: 38  
Listed functions:
Printer friendly API declarations
Word Index links for this example:
Translate this page:
  Spanish    Portuguese    German    French    Italian offers instant, free translations of text or web pages.
User Contributed Notes:
There are no notes on this subject.

Copyright 2001-2017 News2News, Inc. Before reproducing or distributing any data from this site please ask for an approval from its owner. Unless otherwise specified, this page is for your personal and non-commercial use. The information on this page is presented AS IS, meaning that you may use it at your own risk. Microsoft Visual FoxPro and Windows are trade marks of Microsoft Corp. All other trademarks are the property of their respective owners. 

Privacy policy
Credits: PHP (4.4.9), an HTML-embedded scripting language, MySQL (5.6.34), the Open Source standard SQL database, AceHTML Freeware Version 4, freeware HTML Editor of choice.   Hosted by Korax Online Inc.
Last Topics Visited (
4 sec.Function: 'RollbackTransaction'
8 sec.Function: 'mixerGetDevCaps'
Function group: 'Windows Multimedia'
18 sec.Function: 'CryptGetKeyParam'
Function group: 'Cryptography Reference'
23 sec.Function: 'GetDefaultPrinter'
Function group: 'Printing and Print Spooler'
28 sec.Example: 'Winsock: connecting to a news server (NNTP, port 119)'
34 sec.Function: 'MonitorFromWindow'
38 sec.Example: 'GDI+: how to make VFP controls visually shake and shudder'
43 sec.Function: 'GlobalLock'
48 sec.Example: 'Using Video Capture: enumerating installed capture drivers'
53 sec.Function: 'SetMonitorContrast'
Advertise here!