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.
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 2014/07/03
Joseph G. Mitzen posted a very interesting (and elaborate <g>) comment on a post from me in 2009: Delphi – for … in on enumerated data types « The Wiert Corner – irregular stream of stuff.
The crux of his post is about consistency of your tools. And clearly, the Delphi team has some work to do in that regard especially when compared to the Python world where consistency is key (and takes a lot of time to introduce new features as a side effect).
He refers to the ADUG post For-in Enumeration | Australian Delphi User Group Members by DaddyHPriest that lists a number of areas where Delphi does not have enumerator support for.
Which reminds me I promised to publish some more enumeration demos showing what kind of code could be eliminated if things became more consistent.
Hopefully this summer gives me a bit more time for that (:
–jeroen
via: Delphi – for … in on enumerated data types « The Wiert Corner – irregular stream of stuff.
Posted in Delphi, Delphi 2007, Delphi 2009, Delphi 2010, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Development, Software Development | 4 Comments »
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.
Take the approach below
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 »
Posted by jpluimers on 2014/05/29
Thanks Samaliani for posting a Delphi GetWinControlName function as answer to Is there a way to get a VCL Control’s name through the windows API?
The cool thing: it works across processes (as long as your own process has ReadProcessMemory rights).
It works from Delphi XE3 and up.
Be sure to also read the comments by Danny Thorpe on the automation framework in Delphi: that might also be a good place to get this information from.
–jeroen
via: delphi – Is there a way to get a VCL Control’s name through the windows API? – Stack Overflow.
Posted in Delphi, Delphi XE3, Delphi XE4, Development, Software Development | 3 Comments »
Posted by jpluimers on 2014/05/06
Apart from the mandatory Joel on Software article about Unicode and Character sets, these two articles are of great value too:
Fun to read from that blog is the Historical Technology section including this article:
–jeroen
PS: The mandatory one is The Absolute Minimum Every Software Developer Absolutely, Positively Must Know About Unicode and Character Sets (No Excuses!) – Joel on Software.
Posted in .NET, Ansi, ASCII, CP437/OEM 437/PC-8, Delphi, Development, EBCDIC, Encoding, ISO-8859, ISO8859, Shift JIS, Software Development, Unicode, UTF-8, UTF8, Windows-1252 | Leave a Comment »
Posted by jpluimers on 2014/05/05
I learned something new today (thanks Vin Colgin) the Delphi Design-Time Component Name is Limited to 63 characters.
Uwe Raabe found out that this an Object Inspector thing due to this constant in DesignIntf.pas:
const MaxIdentLength = 63;
It has been probably there since Delphi 1 and has been documented on-line since at least Delphi 2007.
I remember having had long (like 100+ character) identifiers in source code, but not in the Object Inspector.
Now I know you can’t (:
–jeroen
via: Vin Colgin – Google+ – Delphi: Design-Time Component Name Limited to 63 characters….
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, Delphi XE5, Delphi XE6, Development, Software Development | 4 Comments »
Posted by jpluimers on 2014/05/05
There is an interesting G+ discussion thread about generic Dictionaries in Delphi.
It covers the stock TObjectDictionary in the Generic.Collections unit, Spring4D, performance characteristics like O(1), O(log n), etc, and implementation details like fill factors and hashing algorithms.
Worth reading at Steve Maughan – Google+ – TObjectDictionary Advice Needed I’ve been using Delphi for….
Since TObjectDictionary hasn’t changed much since the introduction of generics in Delphi, this discussion is valid for at least Delphi XE and up (and probably Delphi 2010 and 2009 as well).
I’m not sure about these last ones as like Andreas Hausladen, I’m cutting back on the Delphi versions I regularly use, which for now are mainly XE6, XE3, XE and 2007).
–jeroen
Posted in Delphi, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Delphi XE5, Delphi XE6, Development, Software Development | Leave a Comment »
Posted by jpluimers on 2014/05/02
One of those StackOverflow gems: permissions – Delphi – setting Full Control on Registry Key – Stack Overflow.
–jeroen
Posted in Delphi, Delphi 2007, Delphi 2009, Delphi 2010, Delphi 7, Delphi XE, Delphi XE2, Delphi XE3, Delphi XE4, Delphi XE5, Delphi XE6, Development, Software Development | 4 Comments »
Posted by jpluimers on 2014/05/02
IP geolocation is hard, and very dependent on where you are in the world. Providers giving different or confusing results are not exceptional.
See the struggle at Dan Sohad – Google+ – Hi! I working in a IP locate app. I’m using as “motors”: … where Dan Sohad tries a Delphi implementation.
–jeroen
Posted in Delphi, Development, Geolocation, Software Development | Leave a Comment »
The Wiert Corner - irregular stream of stuff 