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you must delete the toolbar files.. see details on Bertil's web site..

http://hem.bredband.net/bertilisberg/paradox/errdocs2/eid230.htm

Has anyone gotten the following dialogue when opening Paradox 9 in Vista?

"An attempt was made to access an unmanned file past its end."

After clicking Ok, the program starts and runs in a fairly stable manner.  When I tried installing higher versions of Paradox in Vista (like the one from the X3 package), the same message comes up and blocks the program from running at all.

John Malcolmson, Burnaby, BC

Refer to the section titled "Defeat Vista's Application Virtualization" in the Paradox 9 on Vista article. That should help.

• http://www.prestwood.com/ASPSuite/kb/document_view.asp?qid=101098

Installed Pdox 7/32 on VHP yesterday.. Ran into errors, and just blanket changed permissions on directories to get running.. Today installing Ultimate32 and will try domain connection and idapi.. hopin it works.. works on every OS to date :)

Grant

Hi, I've just downloaded your trial version of psSendMail to run with Paradox 9.  It appears to work fine and be just what I need - EXCEPT.  When I run it on a Vista machine and send HTML emails, it just seems to send plain text.  Yes, I do have the HTML flag set to True - works great with XP.

Your help appreciated.

Regards

Martin Evans

I was also asked recently, why we no longer develop websites for 800x600 resolution. The reason is quite simply that according to w3schools.com, as of January 2008 86% of the web surfers are using a resolution of 1024x768 or higher.

• http://www.w3schools.com/browsers/browsers_display.asp

I was asked recently why we removed Netscape from our standard list of browsers we design pages for. The reason is that Netscape is no longer supported by Netscape. Refer to the following page for more information:

• http://browser.netscape.com/

I was asked recently why we removed Netscape from our standard list of browsers we test against. The reason is that Netscape is no longer supported by Netscape. Refer to the following page for more information:

• http://browser.netscape.com/

Today I cleaned up this articles code (re-pasted from my P9 book).

Hi Graham,

>>...customer in a Customer table and orders would be in an Orders table?

Yes customers in customer table and orders in the orders table as usual.

>>...how many orders have been placed by a specific Customer belong in the Customer library (class) or in an Orders library?

Since Number of Orders is a property of a customer, I would put that property in the Customer class but you are correct that that custom method would indeed count the values from the orders table. It uses the orders.db table. Although classes frequently map 1 to 1 to tables in a database, when creating reusable code, you need to switch your thinking. You need to switch from a data-centric view to an object-centric view.

>>Or would you have a method in Customer.lib which called a method in Orders.lib?

If I wanted the ability to retrieve the number of orders of a customer in the Orders class, sure, you could design it that way. And yes, you could use aggregation where the Customer class "has a" orders object in it. In ObjectPAL, you would have to simply make use of an Orders.lib custom method.

• Aggregation vs. Composition

Interesting article.

I feel the example based on interrogating the 'Customer' table to find out how many orders have been placed somewhat dubious in terms of database design - surely you would only have one record per customer in a Customer table and orders would be in an Orders table?

As far as OO design goes would a method to find out how many orders have been placed by a specific Customer belong in the Customer library (class) or in an Orders library? Or would you have a method in Customer.lib which called a method in Orders.lib?

Well Played.

mOM

Also of note...

In Delphi for .Net, there is no difference between virtual and dynamic.

Here is the syntax in question:

function Age: Integer; Abstract; //Does not work.

The above returns the following error:

[Pascal Error] poc_ClassTestsUnit1.pas(23): E2167 Abstract methods must be virtual or dynamic

Here is the correct syntax:

function Age: Integer; Virtual; Abstract; //Optimized for speed and most common.

function Age: Integer; Dynamic; Abstract; //Optimized for size.

For example, here is a complete simple class example:

  TMyClass = class(TObject)
  private
    function Name: String;
  public
    function Age: Integer; Abstract;
  end;

Then in a descendent class, you implement it:

//Class declaration...

TMyClass2 = class(TMyClass)

public

  function Age: Integer;

end;

//Method implementation...

function TMyClass2.Age: Integer;
begin
  Age := 12;
end;

For more information on the history of Pascal Casing:

• History of Pascal Casing by Brad Abrams

Once you've tried the above suggestions at some point you have to give up and request free support from MS. The link below will get you to the starting point:

http://forums.microsoft.com/TechNet/ShowPost.aspx?PostID=3069333&SiteID=17

It does collect information from your specific computer that will help MS help you.

General tips from MS:

http://support.microsoft.com/kb/947366

Tip: Check your hard disk for errors

http://windowshelp.microsoft.com/Windows/en-US/Help/bc1393cf-9f9c-79c7-0f91-9337c2c41f811033.mspx

Tip: Before applying SP1, make sure all current updates have successfully installed. If you have any failed updates, resolve that PRIOR to attempting to apply SP1.

Tip: Before applying SP1, make sure you have registered your copy of Vista with Microsoft.

Great tip about a grammatical detail often confused!  I like the "he/him" example; makes it easier to remember.

Additional tip:  When dealing with plural "hims," like "people," it's become acceptable to replace the who/whom confusion with a simple "that."  Ex:

People that like Delphi are geniuses.

An aside (and a tip of the hat to waterfall methodology):

Larry, a good friend, and very competent developer, had a modest, personal software project to do.  Because he was both the developer and "consumer," he was able to use the waterfall method to good effect.

In fact, his approach was a little unusual:  He used HelpScribble to create the entire help system before he wrote a single line of code!  The resulting help system, then, became his requirements specification.

I wouldn't suggest that approach for any very ambitious project, but in his unusual case, it worked very well.

Ramesh,

Great post on technical writing!  I find myself agreeing with everything you say, with one small exception:

"This life cycle is similar to the waterfall model of the software life cycle."

It is true that technical writing can follow a cycle similar to the old waterfall software life cycle, but, as with software development itself, I'd hate to approach technical writing that way in the modern world of agile software development.

The waterfall model called for all requirements to be known, and well documented, before development begins. Then, an iteration of the software wass created according those known requirements - and only those requirements.  New requirements would be introduced only after the first iteration was completed.

That model had the advantage of making the developer's, and tech writer's worlds very "safe," but it made for painfully slow development, and often led to initial (and sometimes terminal) customer dissatisfaction.

Agile development methodologies, on the other hand, recognize that all requirements may not be known, that it is rare to "get it right" the first time, and introduce the flexibility to iteratively discover, and manage, requirements as development moves forward.

I find it useful, then, in my technical writing, to track the agile process (PSDP, in this organization), and to use authoring tools that integrate comfortably with our development systems.

A good example of such a tool is HelpScribble.  It includes add-ins for the Delphi development system that allow us to rapidly connect elements of the software to the relevant help topics. Help & Manual is another such tool. 

Both are capable of producing WinHelp, Compiled HTML Help (chm), web documentation, and source for printed manuals, all from a single "project" file.

Additionally, they can parse source code, and produce a very satisfying documentation framework for classes and other elements related to "API" concerns.

The project source from either of these tools can be added to the same version control system used by the software developers, making it easy to track and manage changes as an agile project moves forward.

I occasionally have to repair a table - I usually notice this requirement when trying to change the default field data; restructure won't work until the table has been repaired. However after my recent experience I would like to recommend that before rebuilding a table, you should backup the corrupted table - obviously to a different location to your normal backups - because if the rebuild fails it is possible to do even more damage.

Usually when I repair a table I just let Paradox rumble happily away until it is finished but yesterday when I started a repair, I opened a new window and began working with another program. In the past, I have always left the Paradox screen open until the repair had finished but when I returned to Paradox this time  I discovered that the program had hung. I used Task Manager to end it, then reloaded Paradox to discover that all my filters had disappeared, my default fields were all empty and four records out of 120,000 had  vanished completely. Presumably, these were the records Paradox was actually working on when the program hung.

Fortunately, the table was backed up immediately before the repair and after copying it back and starting the repair again everything worked perfectly. But because of this I would heartily recommend:

1) Backup the table immediately prior to the repair.

2) Don't run anything else while Paradox is repairing.

I'm using Paradox 10 under Vista.

Thanks Wes for adding to this code snippet. Mucho appreciated!