Delphi

When creating an association in ECO you are not guaranteed the order in which the objects at the end of the association will be presented.  For this reason ECO provides a...

Not only is Application.ProcessMessages quite long to type, often extra functionality needs to be called when its used.  To this end I have created two basic wrappers which...

In this article I’ll use the term “Identity” interchangeably to note Auto generated (from RDMS) values usually for a column representing the primary key of a table. These...

You will need the function in this article (http://www.howtodothings.com/ViewArticle.aspx?Article=760) to get this working properly function ParamExists(const ParamName: string):...

(* GetParameterValue GetParameterValue will return the value associated with a parameter name in the form of /paramname:paramvalue -paramname:paramvalue and /paramname -paramname ...

function GetFileSize(const FileName: string): Integer; var   sr: TSearchRec; begin   Result := 0;   if FindFirst(FileName, faAnyFile, sr) = 0 then   begin...

Have you ever found yourself adding the same code to different forms?  Well now you can use the following as a base class for all forms. ===============   BEGIN...

Personally I find both the WinAPI MessageBox and Application.MessageBox and MessageDlg functions cludgy and always add the following function to every app. function MsgBox(const...

The following function will attempt to remove the read only flag on a file, you will need the function in this article (http://www.howtodothings.com/ViewArticle.aspx?Article=755). ...

The following function will return True if a file is read only. function IsReadOnly(const FileName: string): Boolean; var   sr: TSearchRec; begin   (* Assume not read...

This is just a quick set of instructions rather than a comprehensive article.  It is a copy of a posting I made in a Borland newsgroup... I'll give you an example of one...

This article demonstrates the basics of how to store and retrieve a Bitmap in an ECO variable. First create an ECO variable in the class you wish to hold the bitmap, for example: ...

With the help of Jonas Hogstrom and Jan Nordén I have written 2 functions to evaluate OCL.First is to evaluate OCL in EcoSpace:  public object EvaluateOclInEcoSpace(IElement...

Here is an example of using different TableStyles depending on the type of the currently selected object in a DataGrid. I have 2 grids, each hooked to ExpressionHandles. I...

ECO allows you to add TaggedValues (name/value pair) to your model at design time.  Here is how to retrieve the value of a TaggedValue at runtime. obj.AsIObject() gives IObject...

This article will explain derived members in ECO.  It's primary purpose is to describe the difference between the ReEvaluateSubscriber and ReSubscribeSubscriber parameters...

The application we are going to build can be used for capturing worktime and breaks during the worktime. The worktime can be captured with multiple clients and the server application...

ECO II has a new feature in Update 2 which makes it easier to see what it is doing behind the scenes. When you run your app you can look in the messages window of the Delphi IDE...

As of D2005 udpate #2 there is a new helper class in the ECO framework named MaxLengthSupportFunctions. Normally when you databind an EditBox for example to an ECO object you...

If you have ever tried reading constraints from an ECO model you have probably noticed by now that there are lots of auto-generated multiplicity constraints. I personally like...

Before updating the database with changes to your objects it is wise to check that the object is in a valid state first.  ECO allows you to model constraints against your...

procedure THtmlMailForm.SendButtonClick(Sender: TObject);begin if FRunning then begin MessageBeep(MB_OK); Display('**** ALREADY RUNNING ****'); Exit; end; FRunning := TRUE; try {...

In a form etc we can evaluate OCL in the DB by using an OclPSHandle, but how do you evaluate OCL in the DB in code? This tip thanks to Jan Norden from Borland. IOclService oclService...

This article will demonstrate how to use code derived associations to implement user-defined class constraints. Code derived association is derived association without provided...

Simple means of making some components data-aware. Alternative data-aware checkboxes (and radiobuttons) that can be arranged more flexibly. Although more recent versions of Delphi...

How do we databind the information from the ExpressionHandle or other handle type into the ASP.NET Repeater control? Took a little double take viewing, but Pete Morris kindly...

This article explains the pitfalls of inheritance, and offers a solution... In this article I will have to use some ficticious class names etc due to the sensitivity of the project...

This article demonstrates a simple example of using recusive OCL within a composite pattern. "To understand recursion we must first understand recursion" [Source unknown] Surely...

Explains what Code Derived Columns are, and how to use them. The focus of this article will be "Event derived columns".  Jan Nordén (Borland) pointed me in...

Controlling your Library Path can be benefitial for a number of reasons, easy reading, sharing network components/libraries, or even for escrowing projects. There is a relatively...

Implementing Shell Search Handler using Delphi The Shell supports several search utilities that allow users to locate namespace objects such as files or printers. You can create...

Howto store the contents of a RichEdit in an EMF files Sometimes, you may want to store the contents of a rich edit control in a metafile. This article outlines an approach that...

This article describes a simple way to set left and right channel volumes separately. Changing Left and Right channel volumes separately: By : Pooia LalbakhshMS in Computer Engineering These...

This example shows how to send HTML emails using Delphi and Indy, with embedded images. uses  idMessage;procedure TForm1.Button1Click(Sender: TObject);var  html: TStrings; ...

Password authentication is used in many systems for authenticating the identity of one or both peers of a connection. This paper will help you design more secure password authentication...

Refactoring is the process of "improving the design of existing code." Learn how to become a faster and more productive refactorer with Castalia. This is the fourth...

A little tip on using COM with Windows Services. Today I tried accessing an XML document from a Windows service.  When I prototyped my classes using a Windows forms app everything...

Learn about the various error finding habits of Delphi developers and how you can overcome bad habits to find errors faster and more efficiently (Originally published at delphi-expert.com...

This article discusses observations on how the most effective developers are able to cut the amount of typing they do nearly in half and gives recommendations on how you can experience...

This article teaches techniques developers can use to navigate code faster and comprehend it better. (Originally published at delphi-expert.com on May 14, 2004) This is the third...

Learn about exceptions and how to write better error handling code. Learn how Castalia can help us write more robust and fault tolerant code. (Originally published at delphi-expert.com...

This article discusses proper usage of temporary variables, motivations for splitting improper variables, and how to use Castalia to automatically split them. I would like to address...

This article discusses Delphi's try..finally construct, when to use, and how Castalia makes it easier to use. (Originally published at delphi-expert.com on March 16, 2004) In a...

How to use FindFirst and FindNext with recursion, for adding filenames and paths to a stringlist How to create a list of the files in a folder and its subfolders In the following...

An example of implementing the Actor/Role pattern in Bold. Role based programming in Bold Bold allows developers to develop OOP applications which persist to a database. This gives...

A small tip showing how to tell windows that your Edit control should only allow numeric entry. If you need a Windows Edit control to only accept valid numbers, but don't want...

This article explains how to detect if a diskette is in the disk drive on NT based systems (w2k, XP)Windows has the habit of requesting the user to insert a floppy. Normally this...

Borland's SelectDirectory browser is quite ugly, here is how to invoke the Windows one instead.uses   ShlObj, ShellAPI; ...... function BrowseForFolder(handle : HWND;...

One of the solutions to spam is a -frequent updated- database with IP addresses that appear to misbehave. This database should, preferably, be random accessible at high speed....

A small example of making derived attributes which are persisted to the database.Persistent derived attributes in Bold Bold's derived attributes are always evaluated in memory,...