Archive for the ‘Delphi 6’ Category
Posted by jpluimers on 2014/08/28
Quiz questions:
- Does the below unit test succeed or fail?
- Why?
procedure TestHResult.Test_EOleException;
var
OleException: EOleException;
IResult: LongInt; // == HResult
UResult: Cardinal; // == DWord
begin
IResult := $800A11FD;
UResult := $800A11FD;
try
OleException := EOleException.Create('message', $800A11FD, 'source', 'helpfile', -1);
raise OleException;
except
on E: EOleException do
begin
if E.ErrorCode = $800A11FD then
Exit;
Self.CheckEquals(E.ErrorCode, $800A11FD, 'E.ErrorCode should equal $800A11FD');
end; // E: EOleException
end;
end;
Read the rest of this entry »
Posted in Conference Topics, Conferences, Delphi, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Delphi XE5, Development, Event, Software Development | 2 Comments »
Posted by jpluimers on 2014/08/22
While updating a project to a more recent version of Delphi, I also updated the JEDI.INC reference.
Note that since writing Delphi – finding the VERxxx define for a particular Delphi version: use JEDI.INC, the Delphi JEDI project moved from SoureForge to GitHub.
The fun thing: JEDI.INC got updated a few months ago to support Delphi XE7 provisionally.
Given the Delphi release cycle of twice a year, the Delphi Carpathia aka XE7 rumours this summer, I presume Delphi XE7 is near because of:
By then the list of Delphi Versionen | Delphi-Treff will likely also be updaed.
I’m anxious to see if the (Dutch + English) BIG Delphi Conference organized by Barnsten and Blaise from September 11-12 in the Netherlands will be part of the launch tour.
Anyway: here is the JEDI.INC portion with defines: Read the rest of this entry »
Posted in Delphi, Delphi 1, Delphi 2, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 3, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi 8, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Delphi XE5, Delphi XE6, Delphi XE7, Development, Software Development | 6 Comments »
Posted by jpluimers on 2014/08/19
Since this did not make it to DelphiFeeds yet: I’ve seen the function PaletteFromDIBColorTable in Graphics.pas go back as far at least until Delphi 2006, and references on the web as far back as Delphi 4.
So: this bug is old, but as it is a security one, make sure you patch soon.
For Delphi XE6, download 29913 BMP Buffer Overflow hotfix – Delphi, C++Builder, RAD Studio XE6.
For older Delphi versions, read this piece that was adapted from the EDN article Delphi and C++ Builder VCL Library Buffer Overflow:
For users of prior versions of Delphi and C++Builder: these steps should be followed to modify the VCL source code and add it to your application.
For each application:
- Add the modified Edit Vcl.Graphics.pas or Graphics.pas or Borland.Vcl.Graphics.pas to your project
- For C++Builder: Under Project | Options | Packages | Runtime Packages, set “Link with runtime packages” to false
- Rebuild your application
Once for the native VCL and .NET VCL:
- Note: Variable names and scoping might be slightly different depending on your product version.
- Edit Vcl.Graphics.pas or Graphics.pas or Borland.Vcl.Graphics.pas
- Locate the function PaletteFromDIBColorTable.
- Add the following code just before the line assigning a value to Pal.palNumEntries when the DIBHandle = 0
if ColorCount > 256 then
InvalidGraphic{$IFNDEF CLR}@{$ENDIF}SInvalidBitmap;;
–jeroen
via Delphi and C++ Builder VCL Library Buffer Overflow.
Posted in Delphi, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi 8, Delphi x64, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Delphi XE5, Delphi XE6, Development, Software Development | Tagged: Buffer Overflow, Delphi, Delphi versions, vcl | 5 Comments »
Posted by jpluimers on 2014/08/12
In the With Statement series:
Lars Fosdal – Code Rants
The dreaded with…
Debugging today, I found another gotcha.
In this case, both Self and DisconnectedClient has a property named ClientIdentifier.
Note the difference for the mouse-over and the evaluation.
–jeroen
Read the rest of this entry »
Posted in Appmethod, Borland Pascal, Delphi, Delphi 1, Delphi 2, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 3, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi 8, Delphi x64, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Delphi XE5, Delphi XE6, Delphi XE7, Development, Pascal, Software Development, Turbo Pascal, With statement | Leave a Comment »
Posted by jpluimers on 2014/08/06
A long while ago, I wrote about a (then overdue post) on .NET/C#: Using IDisposable to restore temporary settrings example: TemporaryCursor class.
I had been using a similar technique in Delphi since before I found out about the [WayBack] TRecall class and thought: I think my TTemporaryCursor is smarter, as it is based on interfaces.
TRecall (and the [WayBack] Vcl.Graphics descendants [WayBack] TBrushRecall, [WayBack] TFontRecall, and [WayBack] TPenRecall) store [WayBack] TPersistent properties using the Assign method. They were introduced in Delphi 6.
Too bad there are only [WayBack] very few people using TRecall as lots of TPersistent things warrant sasaving and restoring.
My [WayBack] TTemporaryCursor (now [WayBack] at bitbucket) class only stores an integer, so it cannot derive from TRecall. Besides it is based on IInterface which got introduced in Delphi 6, but was present as IUnknown since Delphi 3 (see [WayBack] Interface It! A quick guide to the ins and outs of interfaces in Delphi. By Jimmy Tharpe).
This means that TRecall could have been based on IInterface, so I wonder why it was not.
Note I’m not the first to publish about such a class (Malcolm Grooves wrote [WayBack] TCursorSnapshot, SwissDelphiCenter has [WayBack] TMyCursor, Nick Hodges published about [WayBack] TAutoCursor), it’s just that it has been in my tool box for so long, and written memento classes that you will see 2 articles on it this week.
In the mean time (this works with Delphi 2009 and up), I also wrote a small class that does similar things for any [WayBack] anonymous method. More on that tomorrow.
Back to TRecall: it is an example of [WayBack] the memento pattern in Delphi. The [WayBack] memento pattern allows you to restore state.
SourceMaking.com a.k.a. [WayBack] Design Patterns and Refactoring is a great site about [WayBack] Design Patterns, [WayBack] UML, [WayBack] AntiPatterns and [WayBack] Refactoring.
Most pattern example code is available in all of the C#, C++, Delphi, Java and PHP languages.
Great stuff!
One of the constructs for restoring state is a [WayBack] try … finally … end construct: it allows you to always execute something in the finally block, for instance restoring the state to right before the try block. Read the rest of this entry »
Posted in Conference Topics, Conferences, Delphi, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 3, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi x64, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Design Patterns, Development, Diagram, Event, Software Development, UML | 14 Comments »
Posted by jpluimers on 2014/07/29
ModelMaker Code Explorer (MMX for short) stores the keyboard shortcuts in the registry.
I’ve had it occur once that somehow most (about 95%) of the shortcuts got lost.
Two thinks I learned from resurrecting the shortcuts:
- MMX writes these settings when you exit Delphi
- Only a few keys (with lots of values under them) store the keys.
To resurrect them,
Read the rest of this entry »
Posted in Delphi, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 5, Delphi 6, Delphi 7, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2014/07/22
Found out where the StackOverflow Pascal has its origins: What happened to comments in syntax highlighter? – Meta Stack Overflow.
Like any syntax highlighter, it is not perfect (only a Delphi compiler driven highlighter would have a chance to be perfect), but it does a pretty good job and gets better over time.
–jeroen
Posted in Borland Pascal, Delphi, Delphi 1, Delphi 2, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 3, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi x64, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, FreePascal, Pascal, Software Development, Turbo Pascal | Leave a Comment »
Posted by jpluimers on 2014/07/16
I used to forget about the difference between Variant and OleVariant, and used them like this:
Use OleVariants for OLE, and Variants for non OLE.
There is no need to manually clear them.
Luckily I was right, as the differences are documented in the Delphi on-line help at OLE-compatible Variant type (the oldest I could find was the Delphi 2010 OleVariant documentation): Read the rest of this entry »
Posted in Delphi, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 3, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2014/06/11
A bit more than a year ago, I wrote about Delphi: you should avoid the with statement as it makes your code less future proof. That caused some nice comments on the blog, and some more on LinkedIn where Paul Foster mentioned it in a thread ‘Jeroen Pluimers makes a case against “with” statements.‘ Both interesting reads, especially the reasons that people use or avoid with, or keep its use in balance. There is one set of comments I want to emphasize: refactoring multiple with statements into a one function and a call per former with. Read the rest of this entry »
Posted in Borland Pascal, Delphi, Delphi 1, Delphi 2, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 3, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi 8, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Pascal, Software Development, Turbo Pascal, With statement | 19 Comments »
Posted by jpluimers on 2014/06/03
Talking about Danny Thorpe: he also posted a nice hint on threading methods for ancient Delphi versions that equally applies to DLL exports in any Delphi version, even any programming environment.
Recently, I had to do some surgery in such a Pre-Delphi 6 application, and I was really happy to remember this answer: it instantly solved some process crashes, and the added logging allowed for investigating the actual cause.
Note that this tip isn’t just a good advice for old Delphi versions.
Even in younger Delphi versions, you have to watch methods that can be called from outside a regular Delphi context, for instance exported methods.
Heck, it applies to virtually any development environment: exceptions usually are very specific to that environment and should never cross a process boundary.
Summary
Take the approach below
- for Execute methods in your own thread classes in Delphi 5 or earlier
- for any method that can be called externally (like DLL exports) Read the rest of this entry »
Posted in Delphi, Delphi 1, Delphi 2, Delphi 2005, Delphi 2006, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 3, Delphi 4, Delphi 5, Delphi 6, Delphi 7, Delphi 8, Delphi x64, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Software Development | Leave a Comment »
The Wiert Corner - irregular stream of stuff 