Using Win32 functions in Visual FoxPro Image Gallery
Code examples:
Custom GDI+ class
GDI+: Implementing image scrolling with inertia
How to change display settings: screen resolution, screen refresh rate
Winsock: sending email messages (SMTP, port 25)
Enumerating devices installed on the local machine
Monitoring clipboard content changes (VFP9)
Using Video Capture: displaying on FoxPro form frames and previewing video obtained from a digital camera
Displaying dimmed window behind VFP top-level form
Storing content of the Clipboard to a bitmap file
GDI+: creating a gradient
Pocket PC: custom RAPI class for operating with files and folders on mobile device
Configuring DEVMODE structure for a printer
Browsing Windows Known Folders (Special Folders)
Creating irregularly shaped FoxPro form using transparency color key
Vertical Label control
How to convert a bitmap file to monochrome format (1 bpp)
How to play AVI file on the _screen
How to load a user profile
Enumerating data formats currently available on the clipboard
How to print FoxPro form
How to draw custom Window Caption on FoxPro form
How to make a VFP form fading out when released (GDI version)
How to prevent users from accessing the Windows Desktop and from switching to other applications
How to print a bitmap file
How to generate GUID values

User rating: 9/10 (1 votes)
Rate this code sample:
  • ~
More code examples    Listed functions    Add comment     W32 Constants      Translate this page Printer friendly version of this code sample
Versions:
click to open
Before you begin:
The result is returned in a format like that of the following sample:
{557cf400-1a04-11d3-9a73-0000f81ef32e}

See also:
  • Generating random UUID values
  • Generating sequential UUID values

  • DO declare
    
    LOCAL cGUID, cGUIDString, cGUID1
    cGUID = REPLICATE(CHR(0), 16)  && 128 bits
    
    IF CoCreateGuid(@cGUID) = 0
        cGUIDString = StringFromGUID(cGUID)
        ? cGUID
        ? cGUIDString
    
        * converting from String back to GUID
        cGUID1 = REPLICATE(CHR(0), 16)
        = CLSIDFromString(STRCONV(cGUIDString,5), @cGUID1)
        ? cGUID1
    ENDIF
    * end of main
    
    FUNCTION StringFromGUID(cGUID)
        LOCAL cBuffer, nBufsize
        nBufsize=128
        cBuffer = REPLICATE(CHR(0), nBufsize*2)
        = StringFromGUID2(cGUID, @cBuffer, nBufsize)
        cBuffer = SUBSTR(cBuffer, 1, AT(CHR(0)+CHR(0), cBuffer))
    RETURN STRCONV(cBuffer, 6)
    
    PROCEDURE declare
        DECLARE INTEGER CoCreateGuid IN ole32 STRING @pguid
    
        DECLARE INTEGER CLSIDFromString IN ole32;
            STRING lpsz, STRING @pclsid
    
        DECLARE INTEGER StringFromGUID2 IN ole32;
            STRING rguid, STRING @lpsz, INTEGER cchMax
    
    

    User rating: 9/10 (1 votes)
    Rate this code sample:
    • ~
    844 bytes  
    Created: 2004-07-15 13:24:36  
    Modified: 2013-10-01 12:23:16  
    Visits in 7 days: 33  
    Listed functions:
    CLSIDFromString
    CoCreateGuid
    StringFromGUID2
    Printer friendly API declarations
    My comment:
    The GUID is a unique 128-bit integer used for CLSIDs and interface identifiers.

    See also Microsoft Knowledge Base Article 269387 How To Obtain a GUID in Visual FoxPro

    * * *
    Having a connection to SQL Server, Guids can be generated with the NewId() function.
    FUNCTION NewGuid() As String
            IF SQLEXEC(1, "SELECT NewId() As guid", "csGuid") > 0
                    RETURN csGuid.guid
            ELSE
                    RETURN NULL
            ENDIF

    Another way is using the Scriptlet.TypeLib COM. Note that you must create a new instance of the class for each Guid to be generated, which probably produces some overhead.
    obj = CreateObject("Scriptlet.TypeLib")
    ? SUBSTR(obj.GUID,2,36)

    After a simple test I can estimate that the COM procedure is 5 to 10% faster than the SQL one (local server); and API is the winner creating GUID 15-20 times faster than COM -- for example, 0.24 seconds versus 4 seconds per 10,000 guids created.

    On the same computer C# code generated 1,000,000 guids in 1.05 seconds.
    Word Index links for this example:
    Translate this page:
      Spanish    Portuguese    German    French    Italian  
    FreeTranslation.com offers instant, free translations of text or web pages.
    User Contributed Notes:
    A.M. | 2006-07-19 15:38:05
    DECLARE INTEGER UuidCreate IN rpcrt4 STRING @UUID

    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 (5.5.44), the Open Source standard SQL database, AceHTML Freeware Version 4, freeware HTML Editor of choice.   Hosted by Korax Online Inc.
    Last Topics Visited (54.163.52.98)
    1.18 min.Example: 'How to retrieve information about a cache entry (Internet Explorer)'
    Google
    Advertise here!