devxlogo

We are an award-winning tech entrepreneurship website where trusted experts can provide value globally.

Since 1998, DevX has helped people start businesses, build websites, and provide enterprise technology to people globally. Interviewing the likes of Microsoft’s co-founder, Steve Ballmer, the publication brings comprehensive, reliable, and accessible insights to the Internet.

devxlogo

Trusted for 26 years

Over 30K Articles

1M+ Readers

Expert-reviewed

10K+ Tech Terms

As seen in:

microsoft logo
business_insider_logo
wired_logo
berkley
arstechnica_logo
hackernoon

The Latest

Shared Database Session

Question: Is there a way to share a database session between calling application and DLL? Not having such a sharing (DLL with DataSet components) increases the number of SQL server

Trying to Modify an Original Program

Question: I commissioned a program that was written in Delphi. I am not a programmer, but an excellent hacker. Is there any way I can get into this program to

Fixed-Width Tables in IE5

Internet Explorer version 5 has significantly better HTML table support than previous versions. Up until now, HTML writers have had to rely on trial and error to make tables render

A Runnable Is Not a Thread

You may come across some situations where implementing a Runnable may have some advantages over extending Thread. If the class you are going to multi-thread is already extending another class,

Declaring Variables Inside an If-Condition

C++ allows you to declare variables just before their use rather than at the top of the enclosing block. Thus, it is legal to declare a variable inside the condition

Load a Text File Into a Memo

Question: How do I read a file on the A: drive into my program and then display the contents into an edit box? Answer: I’m not sure you’d want to

Descendants of TTreeNode Not Compatible

Question: I am having troubles with the TTreeView component and adding custom derivations of TTreeNodes to it. I want to define a new type of TTreeNode with a lot of

Refreshing the Desktop

Question: How do I refresh the desktop after I draw on it? Answer: Simple: call the Invalidate method for your form, and the window will refresh.

Type-Declaration Characters

Question: I’m having problems passing variables to an API function. I always receive a Type mismatch error. I reproduced the situation in Visual Basic and found that if I used

Different Versions of Delphi and the BDE

Question: Is it possible to have two different versions of the Borland Database Engine (BDE) installed on the same machine? I’ve been developing in Delphi 3, recently went to Delphi

Open Database Error

Question: I am updating an application that was developed to make an executable test version. However, the live database is opened, not a test database. I have made a test

Drop Word Documents Into FrontPage 98

If you have a Microsoft Word document that you want to insert into an HTML page in FrontPage 98, you don’t have to open Word to convert to HTML. With

Writing an Event Producer

An event producer is also known as the “source” of the event. Java does not define a base class or an interface for the event producer. However, the Listener design

Implementing the EventListener Interface

The EventListener interface is a marker or tag interface that doesn’t define any methods. Its purpose is to provide a base interface for all event listener objects that follow the

Automate E-mail with VBScript

If you have Simple Mail Transfer Protocol (SMTP) installed with Internet Information Server (IIS), you can automate e-mail through VBScript. The Collaboration Data Objects for Windows NT Server (CDONTS) component

Detecting Double-Clicks

When creating a Java GUI, it is often the case that you want some action to be taken when the user double-clicks on some component. Although there is no simple

Helpful VBScript Date Functions

VBScript has some neat date functions. For example, if you want to display a database date field such as “3/14/99” as “Sunday, March 14, 1999”, try this code: Dim dtTemp,

Applying CSS Styles Across Your Entire Site

Using Cascading Style Sheets (CSS), you can easily create styles that apply to the entire site. This technique has many advantages over repeating the same style text over and over

Hashtable Key Replacement

Most Java programmers know that adding an object to a Hashtable using a key already stored in the Hashtable will cause the previously-added object to be “dropped” from the table

Prefer Initialization to Assignment of Objects

In general, assignment requires the creation and destruction of a temporary object, whereas initialization does not. This is true for not just for strings, but for every object type, so

Simulating Virtual Constructors

A constructor may not be declared virtual. The easiest way to simulate virtual construction is by defining a virtual member function that returns a constructed object of its class type:

Member and Non-Member Overloaded Operators

Most of the overloaded operators can be declared either as non-static class members or as non-member functions. In this example, operator == is overloaded as a non-static class member: class

Create Automatic Hourglass Cursors

If you create an ActiveX control that uses a custom MousePointer property, place the control on a form, and at run time change the Screen.MousePointer property to an hourglass. You’ll

Translate Color Values

With the RGB function, VB provides a neat and valuable tool for converting separate Red, Green, and Blue values into a single Long color value.. However, VB won’t let you

Extend Intrinsics in UserControl Wrappers

Sometimes you might want to create autoselecting combo boxes, like those in Intuit Quicken or Microsoft Access, where items in the list are selected as you type. Typically, techniques to

Provide Status Messages for Menus

Subclassing a form lets you give a helpful message whenever a user highlights a menu item. Use the Caption property to identify the menu item, then display the help message

Access Properties Only Through the Object Browser

You can access certain properties of forms, modules, classes, and events within them only through the Object Browser. To see and update the properties, right-click on the element and select