The Wiert Corner – irregular stream of stuff

Jeroen W. Pluimers on .NET, C#, Delphi, databases, and personal interests

  • My badges

  • Twitter Updates

    • RT @ben_a_adams: One of the advantages of more parts of the .NET VM moving from C++ to managed C# is its easier to contribute to. For exam… 21 minutes ago
    • RT @whitequark: WD Red, WD Green, WD Black, WD-40 31 minutes ago
    • RT @maikeltjeonline: Is er al een aanspreek/hulppunt zoals de Woonbond of WOON! voor huiseigenaren met problemen zoals Erfpacht of WOZ bezw… 42 minutes ago
    • RT @BPlaatje: Kerels met standpunten over abortus. Mensen met een topinkomen over werkers. Politici met gegarandeerd wachtgeld over de WW.… 48 minutes ago
    • RT @FTM_nl: Interview | China-deskundige Frans-Paul van der Putten: "Nederland doet er alles aan om Chinese bedrijven hiernaartoe te halen.… 50 minutes ago
  • My Flickr Stream

  • Pages

  • All categories

  • Enter your email address to subscribe to this blog and receive notifications of new posts by email.

    Join 2,280 other followers

Archive for April 17th, 2018

TTemporaryFileStream – via DELPHI AREA » How to have a temporary stream, with no size limit

Posted by jpluimers on 2018/04/17

I needed a TTemporaryFileStream and found it at [WayBackDELPHI AREA » How to have a temporary stream, with no size limit.

It taught me that CreateFileA and CreateFileW (the ANSI and Unicode versions of [WayBackCreateFile function (Windows)) accept a FILE_FLAG_DELETE_ON_CLOSE parameter, so as soon as you close the handle, Windows will dispose of the file.

Note however that this will apply to the file handle so if you want to open it multiple times, you need [WayBackDuplicateHandle function (Windows) as per [Archive.isThe FILE_FLAG_DELETE_ON_CLOSE flag applies to the handle, also known as the file object, which is not the same as the file – The Old New Thing


Posted in Delphi, Development, Software Development, The Old New Thing, Windows Development | Leave a Comment »

Why you should try to avoid using Variant operations in Delphi

Posted by jpluimers on 2018/04/17

[WayBackDelphi “WAT?!” of the day: var v1, v2: Variant; begin v1 := True; v2 := True… shows some interesting code.

The [WayBackVariant Types (Delphi) – RAD Studio: Variant Type Conversions (and the decimal point/comma handling or rounding issues not documented there) usually kill you and are the most important reason to avoid Variant operations in Delphi.


// Delphi "WAT?!" of the day:
v1, v2: Variant;
v1 := True;
v2 := True;
Writeln(v1 + v2); // -2

Posted in Delphi, Development, Software Development | 5 Comments »

%d bloggers like this: