Using Win32 functions in Visual FoxPro Image Gallery
Code examples:
How to build UDP responder
How to put a horizontal text scrolling on the form (a news line, marquee)
Monitoring clipboard content changes (VFP9)
How to find which fonts Windows uses for drawing captions, menus and message boxes
Monitoring changes in a directory
Reading and setting system access privileges for the current process
A procedure for setting file times
Browsing Windows Known Folders (Special Folders)
Custom HttpRequest class (WinINet)
GDI+: Scrolling through large image using the mouse
How to create non-blocking Winsock server
How to print a bitmap file
Accessing examples contained in this reference through Web Services
Winsock: retrieving Web pages using sockets (HTTP, port 80)
Adding user-defined items to the Control Menu of VFP form (requires VFP9)
Scanning the hierarchy of child windows down from the main VFP window
Displaying the associated icons and descriptions for files and folders
Exporting DLL icon resources as .ICO files
How to view icons stored in executable files (Icon Viewer) - II
Storing the environment strings in cursor
How to copy the image of a form to the Clipboard using Bitmap API functions
Placing On-screen Alert on top of all windows
Using FtpCommand
GDI+: custom Clock Control
How to create MD-5 and SHA-1 hash values from a string

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
click to open
Before you begin:
Test the presented class as follows:
obj = CREATEOBJECT("TheHash")

? obj.CreateSHA1("test string")

* returns 661295C9CBF9D6B2F6428414504A8DEED3020641

? obj.CreateMD5("test string")
* returns 6F8DB599DE986FAB7A21625B7916589C

See also:
  • Simple class that encrypts and decrypts files using Cryptography API Functions
  • CryptoAPI: Collection of Providers class
  • WinINet function CreateMD5SSOHash
      Members area. Log in to view this example.
      User name:
      Forgot your password?
      Sign up for
    the Membership
      Buy this example for $10.00
    Instant email delivery.


    User rating: 0/10 (0 votes)
    Rate this code sample:
    • ~
    3548 bytes  
    Created: 2005-03-07 15:21:11  
    Modified: 2013-09-20 13:30:28  
    Visits in 7 days: 17  
    Listed functions:
    Printer friendly API declarations
    My comment:
    Transact-SQL HASHBYTES() function computes MD5 and SHA1 hashes identical to those produced by VFP and C# code samples above.

    * * *
    One-way hash functions can be used for creating a fingerprint for a block of data.

    Also hash functions can be used to evaluate passwords. In Users table of your FoxPro application you store not passwords but their hash values.

    It is extremely difficult, if ever possible, to find the original string for a given hash value -- depends on the hash algorithm as well as computer power and methodology you have.

    * * *
    Message Digest: The representation of text in the form of a single string of digits, created using a formula called a one-way hash function.

    One-Way Hash Function: An algorithm that turns messages or text into a fixed string of digits, usually for security or data management purposes. The "one way" means that it is nearly impossible to derive the original text from the string.

    Hash Collision: More than one input message producing identical hash output.

    * * *
    Secure Hash Algorithm, a hash function developed by the NSA for use with NIST Digital Signature Standard (DSS). NSA almost immediately developed a minor change known as SHA-1. Both SHA and SHA-1 produce a 160-bit digest. SHA-1 is used in SSL.

    * * *
    MD-5 is a one-way message-digest hash function. The algorithm processes input text and creates a 128-bit message digest which is unique to the message and can be used to verify data integrity.

    MD-5 was developed by Ron Rivest and is intended to be used in digital signatures applications. Earlier message digest algorithms include obsolete MD-2 and MD-4.

    See also:
  • RFC 1321 - The MD5 Message-Digest Algorithm
  • What are MD2, MD4, and MD5?
  • Example C Program: Creating an MD-5 Hash From File Content.
  • MD5 Online Cracking using Rainbow Tables
  • RFC 3174 - US Secure Hash Algorithm 1 (SHA1)
  • More on Newly Broken SHA1 on Alex Feldstein"s blog
  • Hash Collisions Q&A
  • 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:
    Malcolm Greene | 2005-04-06 00:16:27
    Are there any Windows version (or service pack) dependencies with this code (advapi32.dll)? I've been burned trying to get the FFC _Crypto class to work across different versions of Windows, re: different flavors of rsaenh.dll. (I noticed that rsaenh.dll is not referenced in above code, but I'm still concerned about the same problem version dependencies).


    Copyright 2001-2015 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 (5.5.46), the Open Source standard SQL database, AceHTML Freeware Version 4, freeware HTML Editor of choice.   Hosted by Korax Online Inc.
    Last Topics Visited (
    14 sec.Function: 'GetProcessHeap'
    34 sec.Function: 'UpdateResource'
    Advertise here!