Using Win32 functions in Visual FoxPro Image Gallery
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GDI+: Storing content of the Clipboard to a bitmap file
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Capturing keyboard activity of another application with the Raw Input API (VFP9)
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Custom GDI+ class
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Using FoxTray ActiveX control: System Tray Icon and menu attached to VFP form
Enumerating raw input devices attached to the system (keyboard, mouse, human interface device)
Copying picture of the active form to the Clipboard using Enhanced Metafile API functions
Using Video Capture: displaying on FoxPro form frames and previewing video obtained from a digital camera
How to play AVI file on the _screen
Storing content of the Clipboard to a bitmap file
Winsock: sending email messages (SMTP, port 25)
How to copy the image of a form to the Clipboard using Bitmap API functions
How to convert a bitmap file to monochrome format (1 bpp)
How to prevent users from accessing the Windows Desktop and from switching to other applications
Custom HttpRequest class (WinINet)
Custom HttpRequest class (WinHTTP)
HOWTO: Use the Win32 API to Access File Dates and Times
Mapping and disconnecting network drives
GetFileOwner - Get the owner of an NTFS file
Retrieving the name of the primary domain controller (PDC) and join status information
How to generate GUID values

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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)
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    844 bytes  
    Created: 2004-07-15 13:24:36  
    Modified: 2013-10-01 12:23:16  
    Visits in 7 days: 51  
    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.
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    User Contributed Notes:
    A.M. | 2006-07-19 15:38:05
    DECLARE INTEGER UuidCreate IN rpcrt4 STRING @UUID

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