The SPS Weblog

Properly Registering Sedna's DDEX Provider

Sat, 01 Mar 2008 15:31:35 GMT

Incomplete Directions
If you read the contents of the Readme.txt that comes with Sedna, you would think that the DDEX Provider can be registered for Visual Studio 2005 by simply shelling out to the command prompt and running the included RegDDEX.exe. Unfortunately, following the outlined steps to the letter will result in very little. In short, the "Microsoft FoxPro Database File (FoxClient)" will not show up in the list when attempting to add a connection from the Server Explorer or when adding a new using the Add New Data Source from the Data menu provided in Visual Studio. Another frustration that many are bound to run into is that the RegDDEX.exe will not even run if you don't have Visual Studio 2005 installed... I don't know about you, but I'm using Visual Studio 2008.

Some Directions That Will Work
We have the source code for RegDDEX.exe and a few quick searches on MSDN will provide a wealth of information on how to install a DDEX Provider. So, what's wrong with what we were given? Well, first off when installing Sedna's DDEX Provider the RegDDEX.exe is responsible for a few basic tasks.

Verify that it can find the Fox Client (Microsoft.Data.FoxClient.dll)
Verify that Visual Studio 2005 is installed (more on this in a moment)
Modify the machine.config file (located in C:\Windows\Microsoft.NET\Framework\v2.0.50727\CONFIG)
Copy Microsoft.Data.FoxClient.dll to the installdir for Visual Studio (such as C:\Program Files\Microsoft Visual Studio 8.0\Common7\IDE)

Machine.config Modification
Near the bottom of the machine.config file you will find a DbProviderFactories node that has a bunch of <add> elements underneath it. The RegDDEX.exe simply adds another element to this list. The element that it adds looks like the following:

What to Change for Visual Studio 2008
If you are using Visual Studio 2008 then you will need to either do the preceding steps manually or modify the RegDDEX project and recompile it. To do the following steps manually, you would copy the Microsoft.Data.FoxClient.dll to C:\Program Files\Microsoft Visual Studio 9.0\Common7\IDE and then add the preceding element to the machine.config file. If you wish to modify the RegDDEX as I did, then go to the source (C:\Program Files\Microsoft Visual FoxPro 9\Sedna\DDEXProvider\Source) and open up the project in Visual Studio. Open the MainModule.vb and modify line 44 to read...

Console.WriteLine(" Unable to detect Microsoft Visual Studio 2008.")

... and modify line 76 to read...

key = My.Computer.Registry.LocalMachine.OpenSubKey("SOFTWARE\Microsoft\VisualStudio\9.0")

Then, recompile the RedDDEX (I renamed mine to RegDDEXVS2008.exe) and run it

After Running RegDDEX
As previously stated, after running RegDDEX the DDEX provider still doesn't show up in the list. Well, the problem is that the Registry still doesn't have all the information it needs. Luckily, this is pretty easy to remedy. In the provided source for Sedna's DDEX Provider there is a file named microsoft.data.foxclient.design.reg. This file is located in the C:\Program Files\Microsoft Visual FoxPro 9\Sedna\DDEXProvider\Source\Microsoft.Data.FoxClient.Design folder. Now, don't run that reg file as-is because there are some problems with it. You'll need to first open it up and note that near the bottom of the file are a bunch of paths that appear to have come from Milind's development machine. You probably don't have Visual FoxPro installed on your D:\ drive and Sedna's install certainly doesn't install the DDEX Provider component's into the VFP 9.0 install directory anyways. So, to fix this registry file you will want to modify the last two entries in it so they read as follows...

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\Packages\{63FBC6D5-9E89-44a0-8C03-3734328EEEB4}]
@="Microsoft.Data.FoxClient.Design.FoxDataProviderPackage"
"InprocServer32"="C:\\Windows\\System32\\mscoree.dll"
"Class"="Microsoft.Data.FoxClient.Design.FoxDataProviderPackage"
"CodeBase"="C:\\Program Files\\Microsoft Visual FoxPro 9\\Sedna\\DDEXProvider\\Microsoft.Data.FoxClient.Design.dll"

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\VisualStudio\8.0\Packages\{63FBC6D5-9E89-44a0-8C03-3734328EEEB4}\SatelliteDll]
"DllName"="Microsoft.Data.FoxClient.DesignUI.dll"
"Path"="C:\\Program Files\\Microsoft Visual FoxPro 9\\Sedna\\DDEXProvider"

What to Change for Visual Studio 2008
Those of you running Visual Studio will need to perform the above step and the additional step of searching and replacing all occurrences of "VisualStudio\8.0" with "VisualStudio\9.0".

Add the Information to Registry
Once you've completed the above steps, regardless of your version of Visual Studio) you will then need to run the microsoft.data.foxclient.design.reg file to add the information to your registry.

Whew - All Done!
If you've followed the steps as outlined here, you should now be able to open up your copy of Visual Studio and add a connection to a Visual FoxPro database. There are lots of cool features provided by Visual Studio's Server Explorer and using the DDEX Provider that is provided with Sedna makes working with VFP data sources a joy. I'm a little disappointed in the RegDDEX and the lack of documentation provided to VFP developers trying to install the DDEX Provider, but it gave me an opportunity to post a cool blog entry and when I get a chance I'll fix this all up by modifying the DDEX Provider project provided out on VFPX. That's one of the things I love about VFP... the VFP Community can provide for themselves.

Until next time... VFP Rocks!

This weblog is sponsored by SweetPotato Software, Inc.

FoxFeeds - Windows RSS Platform for VFP

Sat, 23 Feb 2008 13:05:56 GMT

Windows RSS Platform

While I could go into detail about the Windows RSS Platform here, it is much easier for me to point you to the source which says in part...

"...As part of the RSS support in Internet Explorer 7, users can discover and subscribe to RSS feeds within the browser. When the user subscribes to a feed, it is added to the Common Feed List, which is available for clients to use in addition to or instead of their own list..."
"...The Feed Download Engine downloads feeds and merges the new items with the existing data in the feed store. Using the Windows RSS Platform, applications can then expose the feed data to the user..."
"...The consumption of feed data varies by application; the Windows RSS Platform makes a variety of scenarios possible by providing easy access to the feed data..."

To read the whole of the above and get some detailed information regarding the Windows RSS Platform you can go to "Introducing the Windows RSS Platform" out on the MSDN. The thing to bear in mind is that just about everything having to do with the Windows RSS Platform is surfaced through the msfeeds.dll, a COM dll that you are likely to find in your C:\Windows\System32 directory.

FoxFeeds

One of the prototypes that I worked on while developing for Sedna was a complete vcx wrapper for msfeeds.dll and an RSS reader application to show it off. This wrapper and RSS reader didn't make the Sedna cut for whatever reason, but Microsoft has been kind enough to give me permission to release it on my own since they didn't use it. The original idea behind the wrapper was to create something very FFC-like in that you could certainly program against msfeeds.dll directly in your VFP program, but a wrapper would make the task much simpler. A wrapper would also provide a wealth of information regarding msfeeds for VFP developers that took the time to explore the wrapper classes contained in the library.

Since then, I've finished fixing a few more bugs and renamed the project FoxFeeds. I came up with the name FoxFeeds as it seemed to fit, and though it is not trademarked, I must tell you that I ran into a few other references to this when I Google searched it later on. Andrew MacNeill once had (maybe still does) a folder in NewsGator called "FoxFeeds" that he used to keep his Fox Community oriented feeds organized, and Calvin Hsia once created an RSS reader that hooked into Outlook that Randy Brown showed at a DevCon keynote. So, it appears that it is a popular name, but I really like the name so, while it may be confusing for Andrew and those who attended the DevCon keynote in 2005, I'm going with it.

Machine Code On Purpose

Some may note some crazy code in the feedevents.prg. While the events of msfeeds can now be hooked in the normal fashion (using EventHandler without EventHandlerEx), there was a time when they couldn't. Calvin Hsia was kind enough to get me real close to the solution in one of his blog posts and you can also see me commenting back to him down in the comments of his blog post. So, if you care to read how the code came about and was used to solve the problem, head on over to the above link. I just wanted you to know that I've left that crazy code in FoxFeeds on purpose because it shows that almost anything is possible in FoxPro, even a little machine code when needed. (The basic technique that I believe Calvin used to come up with the proper machine code was to compile a C\C++ project that did what he wanted and then he decompiled it... just a guess, but I think that's about right. Pretty damn ingenious, I might add!)

In Closing

I think the vcx provided in the download when coupled with the RSS reader example pretty much speaks for itself, so I won't be going into any serious detail about the wrapper or the Windows RSS Platform in this post. If you want to figure out how it works, simply put it into debug mode and step through the code. You'll be able to see that Microsoft did a pretty good job of creating a platform that developers can leverage when they created msfeeds.dll. While the RSS Platform isn't perfect, I think you can see that it makes creating an RSS reader a walk in the park.

Perhaps the download serves to enlighten some developers to the existence of the Windows RSS Platform that hadn't heard of it before (came out with IE 7), or, the very least, it could make a few programming tasks easier for those needing to work with msfeeds.dll. Or, conceivably, we could continue adding functionality to FoxFeeds until we had a first class open-source RSS reader for the Windows platform (the example was mostly to show how to use the wrapper - and yes, perhaps maybe to show some outside of the community that a VFP application can not only work great, but look great doing it). Whatever its worth, I present it here so that you can freely download it.

Download FoxFeeds Wrapper and RSS Reader Example (approx. 205 KB)

Until next time... VFP Rocks!

This weblog is sponsored by SweetPotato Software, Inc.

VFP Database Backup Made Simple

Fri, 22 Feb 2008 14:08:23 GMT

Backing Up Data

One of the most important and simplest things a user of a desktop database application can do is to maintain a current backup of the application's database. However, if the user doesn't have some sort of software or hardware that makes an automatic backup on a schedule it is usually up to the software developer to implement an easy to use backup feature for the application.

Implementing Data Backup

There are a number of things to consider when implementing a database backup for an application, but usually the VFP developer simply wants the ability to compress VFP data files from a directory on a schedule (such as every night at 3:00 AM) into a zip file that is stamped with the date and time. In the interest of meeting these modest requirements I present an application I call DataBackup.exe.

DataBackup.exe utilizes vfpcompression.fll to generate a zip file of the Visual FoxPro data files contained in a directory. The directory to backup is specified by simply modifying the path in DataBackup.ini. And, with the help of Windows Task Scheduler (yes, it's available on earlier versions of Windows), DataBackup.exe can easily be run on a schedule. In fact, in the interest of the latter, DataBackup.exe was designed without any GUI elements, though there is a Progress function that you can hook into if you want to implement some progress indication when a backup is in process. In any event, DataBackup.exe is designed to be easily implemented for any VFP application that uses a directory to contain all of the data files.

So, simply bundle DataBackup.exe with your VFP application install. Then have your VFP application write out the path to the Data directory into a DataBackup.ini file where DataBackup.exe resides. Set up a Scheduled Task for it automatically or walk the user through setting up a Scheduled Task that will run DataBackup.exe on a regular schedule.

Note: The Backups (datetime stamped zip files) are generated in the same directory where the DataBackup.exe resides. Also, should DataBackup fail due to an exception being thrown, DataBackup will save the error message information into a file named DataBackup.err. This file can prove useful when trying to diagnose problems when the DataBackup.exe is not generating backups as intended on the user's machine.

Possible Improvements

There are a number of things that could be done to enhance DataBackup.exe, such as adding a Restore feature, providing for multiple directories to be specified in DataBackup.ini, allowing for subfolders, allowing the file mask to be modified via the DataBackup.ini to provide for backing up other types of files, allow the user to specify where the backups are created... Any other ideas?

Download the DataBackup Application (approx. 68 KB)

Until next time... VFP Rocks!

This weblog is sponsored by SweetPotato Software, Inc.

VFPCompression Update - Relative Path Fixes

Fri, 22 Feb 2008 13:35:29 GMT

VFPCompression Update

This update contains fixes to problems surrounding relative paths when compressing folders and files that are not relative to one another or the zip file being created. Previous to this version developers needed to send in .T. for the lIgnorePath parameter when calling functions in order to zip files and folders that were not relative. This was not an acceptable workaround as the relative pathing for subfolders would then be ignored as well. This has been a stumbling block for some in implementing this FLL, so I am glad it is finally fixed and sorry that it took so long for me to address this problem.

Special thanks go out to Sergey Berezniker and Elliot Selick. They independently reported the relative pathing issues and helped with testing once I had addressed the issues.

Sample code for using the library and the library documentation can be found in my previous post. Here's the customary download link...

VFP Compression Update:

VFPCompression FLL Download (35 KB approx.)

This weblog is sponsored by SweetPotato Software, Inc.

VFP Studio - Code Editor Screencast

Wed, 20 Feb 2008 16:41:30 GMT

VFP Studio

Since posting the countdown, I've been fielding lots of questions regarding VFP Studio. Some of the mystery surrounding VFP Studio has been on purpose and some of it has been because we (Bo Durban and I) are not yet sure what all is possible working within the framework provided by Microsoft via the Visual Studio Isolated Shell. However, in order to provide a little more transparency and begin the process of getting feedback from the community I will be presenting a series of screencasts in the next few months. Here I present the first screencast in the series on VFP Studio's Code Editor.

VFP Studio's Code Editor, which is made possible via a Language Service Bo Durban and I created in Visual Studio 2008, provides some significant enhancements when compared to the editor included in VFP 9.0 including outlining, Quick Info, Intellisense for user-defined classes, line numbers, word wrap, VS-style navigation bar, improved Code Snippets and various other features we are implementing in to VFP Studio. In any event, here's the screencast. Enjoy.

Link to View the Screencast Online:

VFP Studio's Code Editor (approx. 9 MB)

Link to Download SWF for Offline Viewing:

VFP Studio Code Editor Screencast in Zip Format (approx. 9 MB)

Until next time... VFP Rocks!

This weblog is sponsored by SweetPotato Software, Inc.

VFP Application Updating Made Simple

Fri, 15 Feb 2008 10:47:31 GMT

02/16/2008 correction: Thanks to Dave Crozier for finding a bug in the code (see comments below). A new zip file of AppUpdate.zip has been uploaded to the server. If you previously downloaded the zip you can download it again or make the change as described in the commments of this blog entry.

Updating Visual FoxPro Applications

One of the things that I tried to do in my article regarding ClickOnce was to provide Visual FoxPro developers with an understanding of one of the many solutions available for updating applications once they have been deployed. While ClickOnce is extremely powerful, there are times when a more home-grown solution can be more appropriate. Updating applications with applications that the developer has written and/or has the source code for can also provide a degree of flexibility and power that just isn't available in solutions such as ClickOnce or Installshield's update service. So, in this blog entry, I'll be presenting an application that I created using Visual FoxPro SP2 that can be used to update virtually any Visual FoxPro application.

AppUpdate.exe

AppUpdate.exe is what is known as a 'Loader'. This basically means that it is responsible for checking for updates, installing them if they exist, and then loading (running) the application it is in charge of updating. Relying heavily on the use of vfpcompression.fll and the new vfpconnection.fll, AppUpdate.exe is designed to allow Visual FoxPro developers to quickly and easily add update capabilities to their applications. Here's a couple of screen shots of AppUpdate runnning...

While I am including the source code for the AppUpdate project, it is not necessary to modify AppUpdate in order to configure it to update a particular application. AppUpdate gets its information from the appupdate.ini file that provides a myriad of sections and entries that will allow you to specify what application it is supposed to load, where to check for updates, how to load the application, what to display to the user, where to copy updates locally so that the same update only needs to be dowloaded once in a multi-user environment, when to display updates, what VFP code to execute once the update has been installed, etc. So, as a developer you really only need to modify the ini to suit and bundle AppUpdate with your VFP applications.

In The Download ...

In the download I am including a fully working example of AppUpdate along with the source. I've included a sampleapp.exe that is version 1.0 and I've placed a live update for it (version 2.0) on the SweetPotato Software server at this end so you'll be able to actually try AppUpdate out and see how it works straight out of the box. I've included copious comments in the appupdate.ini file that you'll want to review and a couple of ReadMe.txt files. Simply dowload the zip file below, extract it somewhere, read through the ini file and the included ReadMe.txt files and then run the included AppUpdate.exe. When you start wanting to create your own updates you can have a look at the ServerUpdate folder I've included in the download as that contains the files that are up on the SweetPotato Software server that are updating the sampleapp.exe provided in the download.

Let Me Know What You Think

If you give AppUpdate a try, I'd love to hear what you think of it. If you have any suggestions for enhancements or find any bugs feel free to leave a comment here and I'll respond.

Until next time… Visual FoxPro Rocks! >

AppUpdate Project and Example Download (922 KB approx.)

This weblog is sponsored by SweetPotato Software, Inc.