Using Win32 (WinAPI) Functions in Microsoft Visual FoxPro

Code sample: How to play MIDI notes

Wed, 09 Apr 2008 19:46:30 EST

Set the note in 0 to 127 range and the velocity (how hard the key is pressed) in 20 to 200+ range and press Enter.

API function: midiOutShortMsg

Wed, 09 Apr 2008 19:37:23 EST

Sends a short MIDI message to the specified MIDI output device.

API function: midiOutReset

Wed, 09 Apr 2008 19:26:27 EST

Turns off all notes on all MIDI channels for the specified MIDI output device.

Code sample: Using WM_COPYDATA for interprocess communication (VFP9)

Thu, 03 Apr 2008 09:25:33 EST

An application sends the WM_COPYDATA message to pass data to another application running on the same PC. The C# and VFP versions of this code sample are functionally identical. That allows exchanging data between .NET and VFP forms (applications).

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Tue, 01 Apr 2008 00:00:00 EST

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Code sample: How to find when the application started

Wed, 26 Mar 2008 18:15:50 EST

The GetProcessTimes function among other output parameters returns the creation time of the process.

Code sample: Obtaining I/O counts for the current process

Wed, 26 Mar 2008 18:10:36 EST

The IO_COUNTERS structure contains I/O accounting information for a process or a job object. For a job object, the counters include all operations performed by all processes that have ever been associated with the job, in addition to all processes currently associated with the job.

API function: GetProcessVersion

Wed, 26 Mar 2008 17:21:24 EST

Retrieves the major and minor version numbers of the system on which the specified process expects to run.

API function: GetProcessTimes

Wed, 26 Mar 2008 17:21:07 EST

Retrieves timing information for the specified process.

Code sample updated: Round FoxPro form

Sat, 22 Mar 2008 11:10:54 EST

C# version has been added to this and two other code samples.

API function: JetDeleteTable

Fri, 11 Jan 2008 17:06:47 EST

Deletes a table in an ESE database.

API function: JetOpenTable

Fri, 11 Jan 2008 17:04:02 EST

Opens a cursor on an existing table.

API function: JetCloseTable

Fri, 11 Jan 2008 17:01:19 EST

Closes an open table in a database. The table is a temporary table or a normal table.

API function: JetCreateTable

Fri, 11 Jan 2008 16:58:01 EST

Creates an empty table in an ESE database.

API function: JetDetachDatabase

Fri, 11 Jan 2008 16:53:42 EST

Releases a database file that was previously attached to a database session.

API function: JetCloseDatabase

Fri, 11 Jan 2008 16:50:28 EST

Closes a database file that was previously opened with JetOpenDatabase.

API function: JetCreateDatabase

Fri, 11 Jan 2008 16:47:17 EST

Creates and attaches a database file to be used with the ESE database engine.

API function: JetCreateInstance

Fri, 11 Jan 2008 13:48:18 EST

Allocates a new instance of the database engine for use in a single process.

API function: JetEndSession

Tue, 08 Jan 2008 18:01:21 EST

Ends the session, and cleans up and deallocates any resources associated with the specified session.

API function: JetBeginSession

Tue, 08 Jan 2008 17:56:09 EST

Starts new ESE session and initializes and returns an ESE session handle

API function: JetInit

Tue, 08 Jan 2008 17:49:56 EST

Puts the database engine into a state where it can support application use of database files.

API function: JetTerm

Tue, 08 Jan 2008 17:49:45 EST

Initiates the shutdown of an instance that has been initialized by JetInit.

API function: if_nametoindex

Tue, 08 Jan 2008 10:55:25 EST

Converts the ANSI interface name for a network interface to the local index for the interface.

API function: if_indextoname

Tue, 08 Jan 2008 10:52:08 EST

Converts the local index for a network interface to the ANSI interface name.

API function: GetTcp6Table

Tue, 08 Jan 2008 10:31:27 EST

Retrieves the TCP connection table for IPv6.

API function: GetWindowRgnBox

Fri, 04 Jan 2008 15:19:55 EST

Retrieves the dimensions of the tightest bounding rectangle for the window region of a window.

API function: PaintDesktop

Fri, 04 Jan 2008 15:09:21 EST

Fills the clipping region in the specified device context with the desktop pattern or wallpaper.

API function: GdiSetBatchLimit

Fri, 04 Jan 2008 13:56:15 EST

Sets the maximum number of function calls that can be accumulated in the calling thread`s current batch. The system flushes the current batch whenever this limit is exceeded.

API function: GdiGetBatchLimit

Fri, 04 Jan 2008 13:51:41 EST

Returns the maximum number of function calls that can be accumulated in the calling thread`s current batch.

API function: GdiFlush

Fri, 04 Jan 2008 13:50:25 EST

Flushes the calling thread`s current batch.

API function: GetProductInfo

Wed, 26 Dec 2007 14:44:45 EST

Retrieves the product type for the operating system on the local computer, and maps the type to the product types supported by the specified operating system.

API function: GetNativeSystemInfo

Wed, 26 Dec 2007 14:20:47 EST

Retrieves information about the current system to an application running under WOW64.

Visits from MS crawler using regular agent string

Tue, 09 Oct 2007 14:07:09 EST

Last several weeks an MS crawler is hitting my website coming from ip range of 65.55.165.10 to approx. 65.55.165.125.

An interesting thing that the agent parameter is a regular one:
Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.2; .NET CLR 1.1.4322)
supposedly pointing at an average web user.

A typical query string look like this:
http://search.live.com/results.aspx?q=functions

The robot's searches are mostly too general and repetitive: functions, foxpro, using, process, windows, registry, connections, language, socket and so on.

http://www.who.is/whois-ip/ip-address/65.55.165.76/

Code sample: How to display a Print property sheet

Thu, 04 Oct 2007 15:43:39 EST

The Print property sheet is a standard user interface that enables the user to specify the properties of a particular print job.

API function: PrintDlgEx

Thu, 04 Oct 2007 15:31:51 EST

The PrintDlgEx function displays a Print property sheet that enables the user to specify the properties of a particular print job.

API function: PrintDlgEx

Thu, 04 Oct 2007 15:31:51 EST

The PrintDlgEx function displays a Print property sheet that enables the user to specify the properties of a particular print job.

Code sample updated: Reading records in Windows Event logs

Sun, 09 Sep 2007 20:45:33 EST

With Event Viewer, users can monitor events recorded in the Application, Security, and System logs.

API function: DeregisterEventSource

Sun, 09 Sep 2007 20:42:25 EST

Closes a write handle to the specified event log.

API function: RegisterEventSource

Sun, 09 Sep 2007 20:40:26 EST

Retrieves a registered handle to the specified event log.

API function: ReportEvent

Sun, 09 Sep 2007 20:35:27 EST

Writes an entry at the end of the specified event log.

API function: GetEventLogInformation

Sun, 09 Sep 2007 20:28:34 EST

Retrieves information about the specified event log.

API function: ClearEventLog

Sun, 09 Sep 2007 20:25:08 EST

Clears the specified event log, and optionally saves the current copy of the log to a backup file.

API function: SetFilePointerEx

Mon, 20 Aug 2007 17:51:44 EST

Moves the file pointer of the specified file.

Watch video: FTP Class Library for Visual FoxPro -- getting started

Fri, 22 Jun 2007 00:23:35 EST

When a control from the FTP class library is dropped on VFP form, the form immediately turns into convenient FTP browser.

Solution added: FTP Class Library for Visual FoxPro

Fri, 22 Jun 2007 00:21:11 EST

The solution presents Visual FoxPro class library that wraps the set of FTP functions in the Microsoft® Win32® Internet (WinInet) API library.

New format of code samples introduced on the site: solutions

Fri, 22 Jun 2007 00:11:39 EST

What we call a solution is more than an advanced code sample. It is an entity containing more than one file, for example, a class library. Solution is meant to be a building block turn-key ready for inclusion in VFP developer's project.

API function: WTSQuerySessionInformation

Fri, 08 Jun 2007 16:35:26 EST

Retrieves session information for the specified session on the specified terminal server. It can be used to query session information on local and remote terminal servers.

Code sample updated: How to display a user-defined icon in the MessageBox dialog

Wed, 30 May 2007 16:43:31 EST

Shell32.dll contains several dozens system icons. Each of them can be easily displayed on MessageBox dialog form via MessageBoxIndirect API call.

Code sample: How to view icons stored in executable files (Icon Viewer) - II

Fri, 25 May 2007 21:54:26 EST

An API ImageList object (different from ImageList ActiveX control) is created and populated with the icons extracted from specified executable or library file. Then the ImageList is linked to a ListView control on the form. Each item in the ListView represents an icon.

Code sample: System Image List Viewer

Fri, 25 May 2007 17:01:44 EST

The OS creates the System Image List for each running process, with the process mainly responsible for populating the list with ListImage items via SHGetFileInfo calls or IExtractIcon Interface and may be by some other means.

Code sample updated: Enumerating files opened on the network

Fri, 25 May 2007 10:54:52 EST

The NetFileEnum function returns information about some or all open files on a server in an array of FILE_INFO_3 or FILE_INFO_2 structures.

Rewritten from scratch to become functional.

User contributed notes, rules changed

Fri, 25 May 2007 08:43:16 EST

Due to constant attention from comment spammers the rules of posting user contributed comments to the articles have changed. Starting recently, only subscribers can do that.

API function: ImageList_GetImageCount

Thu, 24 May 2007 18:45:53 EST

Retrieves the number of images in an image list.

API function: ImageList_Remove

Thu, 24 May 2007 18:44:34 EST

Removes an image from an image list.

API function: ImageList_Add

Thu, 24 May 2007 18:44:25 EST

Adds an image or images to an image list.

API function: ImageList_GetIconSize

Thu, 24 May 2007 18:43:42 EST

Retrieves the dimensions of images in an image list. All images in an image list have the same dimensions.

API function: ImageList_Create

Thu, 24 May 2007 18:40:51 EST

Creates a new image list.

API function: ImageList_Destroy

Thu, 24 May 2007 18:35:06 EST

Destroys an image list.

Code sample: Displaying the associated icons and descriptions for files and folders

Thu, 17 May 2007 18:48:21 EST

When the list of files and folders is to be displayed inside a VFP form, the ListBox VFP control and the ListView ActiveX control are probably the first two candidates for the job.

The ListBox`s presentation style can only be described as the minimalistic :) , while the ListView shows items in much fancier manner, and can even accompany each file and folder with an icon.

And an imminent question arises: where are those icons stored and how to put them to work?

API function: Shell_GetImageLists

Mon, 14 May 2007 11:45:49 EST

Retrieves system image lists for large and small icons -- undocumented.

API function: SHGetFileInfo

Sat, 12 May 2007 20:15:49 EST

Retrieves information about an object in the file system, such as a file, a folder, a directory, or a drive root.

The most obvious application for this function is obtaining the default icon (HICON handle) for a given file type.

Syntax coloring on web pages with GeSHi - Generic Syntax Highlighter

Tue, 08 May 2007 08:59:33 EST

Since yesterday news2news web site displays all code samples in colored syntax, including VFP, VB.Net, C#, C++ and WMI versions.

The web pages definitely look less dull, which is achieved with a help of GeSHi - Generic Syntax Highlighter plus some minor tweaks on top.

Code sample: Displaying the color pallete stored in an image file

Tue, 01 May 2007 20:44:14 EST

Depending on its bit per pixel mode, an image file can store a color palette inside its data. GDI+ functions GdipGetImagePalette and GdipGetImagePaletteSize allow to retrieve the palette in a form of ColorPalette structure.

API function: GdipSetImagePalette

Tue, 01 May 2007 20:42:53 EST

Sets the color palette of this Image object.

API function: GdipGetImagePalette

Tue, 01 May 2007 20:39:41 EST

Gets the color palette of this Image object.

API function: GdipGetImagePaletteSize

Tue, 01 May 2007 20:32:45 EST

Gets the size, in bytes, of the color palette of this Image object.

Code sample: How to make a VFP form fading out when released (GDI version)

Mon, 30 Apr 2007 23:14:07 EST

When a VFP form is released, usually it disappears immediately. Wouldn`t it be nice to have the form slowly (or less slowly) fading out?

API function: GetWorldTransform

Mon, 30 Apr 2007 13:38:58 EST

Retrieves the current world-space to page-space transformation.

API function: DPtoLP

Fri, 27 Apr 2007 13:03:27 EST

Converts device coordinates into logical coordinates.

API function: LPtoDP

Fri, 27 Apr 2007 12:59:53 EST

Converts logical coordinates into device coordinates.

API function: ClientToScreen

Fri, 27 Apr 2007 11:58:15 EST

Converts the client-area coordinates of a specified point to screen coordinates.

API function: GetMapMode

Fri, 27 Apr 2007 09:46:50 EST

Retrieves the current mapping mode.

API function: SetMapMode

Fri, 27 Apr 2007 09:45:41 EST

Sets the mapping mode of the specified device context.

API function: SetGraphicsMode

Fri, 27 Apr 2007 09:34:31 EST

Sets the graphics mode for the specified device context.

API function: GetGraphicsMode

Fri, 27 Apr 2007 09:28:38 EST

Retrieves the current graphics mode for the specified device context.

Code sample: How to make a VFP form fading out when released

Sun, 15 Apr 2007 19:38:56 EST

When a VFP form is released, usually it disappears immediately. Wouldn`t it be nice to have the form slowly (or less slowly) fading out?

An obvious way of doing that is covering the form with another window, which holds the image of the original form. Once covered, the original form disappears. After that the covering window gradually changes its opacity (alpha channel) from opaque (255) to completely transparent (0).

Code sample: GDI+: how to make VFP controls visually shake and shudder

Sun, 11 Mar 2007 12:38:30 EST

Shuddering control may appear a good way to get user`s immediate attention. For example, when Purchase Order form opens, and the shipping date is not entered or overdue, the textbox hosting this value may start vibrate and thus can be easily spotted by the user.

See a short demo displaying a form with several controls (Adobe Flash Player is required).

VFP forum opens on this website

Wed, 07 Mar 2007 16:52:11 EST

The forum becomes a part of the main website -- Using WIn32 Functions in Visual FoxPro.

The main topic on the new forum is, no doubt, Windows programming in Visual FoxPro: calling Windows API functions, creating DLLs and FLLs, using Visual FoxPro API.

The registration process is simple: provide an email address, select user name and password.

The forum is powered by phpBB -- a high powered, fully scalable, and highly customizable Open Source bulletin board package -- http://www.phpbb.com

Code sample: GDI+: rotating images using Matrix transformations

Tue, 06 Mar 2007 18:58:29 EST

Links section has been updated

Tue, 06 Mar 2007 15:02:44 EST

Visitors to the web site now can suggest VFP Internet resources to be displayed in the Link section.

Code sample updated: Custom GDI+ class (requires VFP8)

Mon, 05 Mar 2007 23:28:48 EST

Several matrix transformation functions are made available through GDIMATRIX class.

API function: GdipInvertMatrix

Mon, 05 Mar 2007 23:23:55 EST

For invertible matrix, replaces the elements of this matrix with the elements of its inverse.

API function: GdipGetMatrixElements

Mon, 05 Mar 2007 23:19:12 EST

Gets the elements of this matrix. The elements are placed in an array in the order m11, m12, m21, m22, m31, m32, where mij denotes the element in row i, column j.

API function: GdipSetMatrixElements

Mon, 05 Mar 2007 23:13:39 EST

Sets the elements of this matrix.

API function: GdipCreateMatrix2

Mon, 05 Mar 2007 23:06:28 EST

Creates and initializes a a 3 ×3 matrix that represents an affine transformation.

Code sample: Playing WAV sounds simultaneously

Fri, 16 Feb 2007 18:30:10 EST

This code was written in response to a question posted on UT: Ride two WAVs at once? As I found, the sndPlaySound was not suitable for this. To play multiple sounds simultaneously, the waveOut* functions must be used...

API function: ReadEventLog

Sat, 10 Feb 2007 12:36:40 EST

Reads a whole number of entries from the specified event log. The function can be used to read log entries in chronological or reverse chronological order.

API function: GetOldestEventLogRecord

Sat, 10 Feb 2007 12:32:32 EST

Retrieves the absolute record number of the oldest record in the specified event log.

API function: GetNumberOfEventLogRecords

Sat, 10 Feb 2007 12:28:51 EST

Retrieves the number of records in the specified event log.

API function: CloseEventLog

Sat, 10 Feb 2007 12:25:44 EST

Closes a read handle to the specified event log.

API function: OpenEventLog

Sat, 10 Feb 2007 12:23:23 EST

Opens a handle to the specified event log.

User note: A.M.

Wed, 07 Feb 2007 13:11:54 EST

There's no such example unfortunately in this reference. As far as I know, NTFS and FAT systems do not support a single location or object that stores names of all files and folders.

http://en.wikipedia.org/wiki/WinFS

User note: tsoda

Wed, 07 Feb 2007 12:21:21 EST

Is there an example for finding the location of a specific filename from within a container of many folders?

Code sample: Using named pipes to pass data between processes

Sun, 21 Jan 2007 21:08:52 EST

This code sample contains definitions of two classes, NamedPipeServer and NamedPipeClient, encapsulating named pipes API functionality. The Pipes, as well as mailslots, can be used for exchanging data between processes running on same computer or on different computers.

API function: SetNamedPipeHandleState

Wed, 17 Jan 2007 14:47:56 EST

Sets the read mode and the blocking mode of the specified named pipe. If the specified handle is to the client end of a named pipe and if the named pipe server process is on a remote computer, the function can also be used to control local buffering.

API function: DisconnectNamedPipe

Wed, 17 Jan 2007 14:42:25 EST

Disconnects the server end of a named pipe instance from a client process.

API function: ConnectNamedPipe

Wed, 17 Jan 2007 14:40:03 EST

Enables a named pipe server process to wait for a client process to connect to an instance of a named pipe.

Code sample updated: How to create MD-5 and SHA-1 hash values from a string

Tue, 16 Jan 2007 21:24:09 EST

C++ version added to this code sample.

Code sample updated: GDI+: enumerating fonts installed on the system

Tue, 16 Jan 2007 21:17:17 EST

C# version added to this code sample.

Code sample updated: Creating the Open dialog box to specify the drive, directory, and name of a file to open

Tue, 16 Jan 2007 21:05:45 EST

C# version added to this code sample.

API function: CreateNamedPipe

Tue, 16 Jan 2007 18:44:28 EST

Creates an instance of a named pipe and returns a handle for subsequent pipe operations.