Sometimes, it’s useful to know whether a control is displaying vertical scrollbars, horizontal scrollbars, both horizontal and vertical, or no scrollbars at all. For instance, when determining the amount of

Most professional and commercial applications exhibit a specific behavior when using dialog boxes with text fields: When you tab to an input field, or hot-key (using some ALT-key combination), you

To keep a list of available error codes in your components, declare a private enumeration: Private Enum Errors InvalidUserID = vbObjectError + 513 InvalidPassword SearchNotFoundEnd Enum Setting the first value

The Winsock control allows you to make only one connection between two computers. However, you can create multiple connections (many computers to one) by creating multiple instances of the Winsock

Question: I am creating an Active Server Pages (ASP) application using Visual InterDev and I need to display data in a non-bound data grid. I have read that it is

Timer controls can be practical when you need to add a small delay in program execution. However, if you need the delay in a class module (instead of on a

When you use Index Server and Internet Information Server (IIS), you get a moderately useful search process built into your Web application. However, it isn’t readily apparent where that data

A vector stores its elements contiguously in memory (although this is not a requirement in the Standard, in practice, all implementations use contiguous storage). Consequently, each element in a vector

When outputting HTML, it’s often handy to be able to turn any URL, such as http://www.whatever.com, into a hyperlink, such as http://www.whatever.com. You can do this with a regular expression

The prominent mechanism used to debug a Java application is to write string messages to System.out. However, this method clutters up the output of the program. In order to turn

Any object that defines the copy constructor, default constructor, assignment operator and destructor as public members (either explicitly or implicitly) can be stored in STL containers. If you do not

By default, instances of Window subclasses such as Frame and Dialog appear at the upper-left corner of the screen when made visible. For a more user-friendly interface, you can center

The DrawEdge API provides a convenient way to draw a number of interesting effects. You can change the EDGE_ constants to give different border effects; the BF_ constants determine which

The tables that you design so carefully could end up looking odd in Internet Explorer or Netscape Navigator. The trouble is that browsers treat empty table cells differently. For instance,

Question: What code do I use for Delphi to run a program and use command line parameters inputted by the user? Answer: This code will allow you to launch other

Exceptions can be used as an alternative control structure in addition to for-loops or while-blocks. For example, you can use exceptions to implement a simple application that prompts the user

If you extend an AWT class to add text to a GUI component, then you probably need access to the font’s metrics so that you can deduce the amount of

A little-known attribute of the tag is TARGET. This attribute can be used to direct the output of a CGI program to another browser window, or another frame in the

Question: How can I determine if is down or up while dragging an object within my app? The goal is to detect if something is being copied or moved. Answer:

Question: I want to develop a free e-mail system similar to what Hotmail and Yahoo offer. I was wondering if you could give me some ideas on how to approach

When creating a query using the Visual InterDev 6 Recordset Design-Time control (DTC) against a Microsoft Access 97 database, you may get an error 80020009. The problem is that the

During reallocation, a container re-constructs its elements in a new memory location and destroys the original elements by invoking their destructor. Since the destructor of auto_ptr deletes its bound object,

In Java, static variables may be used as flags to maintain state between different instantiations of a class (see Tip: “Using Static Variables to Store State Across Instantiations”). However, the

Question: I want to set up my NT Server as my primary domain server. How do I do it? Answer: Unfortunately, the only way I know to convert a current

Question: When implementing the Microsoft DNA model, it is suggested to create objects with methods only (no properties) to maintain true stateless objects. If an object will only live for

Question: Can we transfer an application from 32 bits to16 bits (PowerBuilder 5.0) without problems ? Answer: The only thing you will have to check for is API calls. The

Question: Is there an easy way to load a datastore with a comma-delimited text file? Answer: Yes, just load the file into memory and do a global search and replace

Question: Is there a way to query NT 4.0 (programmatically or manually) to have it tell me whether it is NT workstation or NT server? Is the answer in the

Question: I’m trying to export a report to Excel with OLE automation. I’m using PB 5.0.2 and Excel 97. I’ve seen countless examples on how to do this (in fact,

Question: How do I add a DOS exe such as ping to a VB program? Answer: If starting another program is what you want, then use the Shell function. The