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Using Expandable Outlines in Netscape

Question: I’ve written a page that uses expandable outlines using the display property of SPAN objects and it works fine in Internet Explorer 4. However, Netscape does not seem to

Trouble With String That Contains a Backslash

Question: I get a string from the Microsoft Index Server like this: “Information uber”. If I try to assign this string to a variable I get a runtime error: “Invalid

Compute Credit Card Check Digits

The last digit in your credit card number is a check digit derived from the other digits using the Luhn Formula as described in ISO/IEC 7812-1:1993. Its primary purpose is

Include Code for Debugging

VB supports conditional compilation, just like Visual C++. However, Visual C++ has a predefined constant named _DEBUG that makes it easy to include code only while debugging, as in this

Nix the X

Sometimes, you want to show a form that you don’t want users to be able to cancel by clicking on the X-it might not make sense for your app. The

Use This Higher-Resolution Stopwatch

Use this code to create a class called HiResTimer: ‘The number is codified as HighPart*2^32+LowPartPrivate Type LARGE_INTEGER LowPart As Long HighPart As LongEnd TypePrivate Declare Function QueryPerformanceCounter Lib _ “kernel32”

Prevent Checkbox Changes

You’ll often want to display a checkbox-style listbox to show users the values they have selected in an underlying database. However, you don’t want to allow users to change the

Call Up Windows Shell Features

Here’s a little routine that provides a quick and dirty way to call up some of the more oddball features of the Windows shell. It works by emulating user keystrokes,

Keep Track of Index Numbers

When using control arrays, I find it difficult to keep track of the index number of each control. Even if I use constants, I often have to look up the

Establish a Data Dictionary

If your SQL looks like this, you need to ask yourself how much code you’d have to inspect and revise if you decided to change a database field or table

Improve on the Bubble Sort

A bubble sort’s execution time is a multiple of the square of the number of elements. Because of this, the bubble sort is said to be an n-squared algorithm. You

Context-Sensitive Help for Disabled Controls

If you want a form to support context-sensitive help, set the WhatsThisButton and WhatsThisHelp properties on the form to True, and set the WhatsThisHelpID property to a corresponding help-file topic

Slam Selected Items Into an Array

Use this code to retrieve all selected list items in a multiselect-style listbox in one API call. It’s a lot easier than iterating through a large list using For…Next. This

Sorting With the sort() Algorithm

The generic algorithm sort() is part of the Standard Library. sort() takes two arguments of type const iterator that point to the beginning and the end of the sequence respectively:

Storing a Last-Modified Date in a Cookie

On informational Web sites, it is often handy to be able to show certain kinds of information only once, and then keep it hidden until it is updated. That way,

Placing a Sound File on a Web Page

Question: I want to put a sound file that I saved on my A drive on my Web page but I don’t know what HTML tag to use. The file

DHTML and XML Courses

Question: Can you recommend a training company that offers DHTML and/or XML courses? Answer: I unfortunately can’t make a specific recommendation because of the nature of what I do, but

Non-Form ActiveX Event Does Not Fire From ASP

Question: I downloaded Microsoft’s DIRWALK VB code and used it to create an ActiveX server. I want it to walk an HTML directory tree with ASP (Active Server Pages) so

Changing a Layer Through a Link

Question: Can I change the text of my layer through a link? I’ve heard it’s impossible and that I have to change the visibility of the layer and replace it

Performing File Operations With the File Class

You can use the File class (see Tips: “Constructing a File Class” and “Manipulating File Names With the File Class”) to perform operations on files that reside on your operating

Manipulating File Names With the File Class

Java defines a File class (see Tip: “Constructing a File Class”) that you can use to manipulate the file name and perform file-related operations on the underlying file system (see

Constructing a File Class

Java defines a File class that represents a name of a file on your operating system’s file system. You can use the File class to manipulate the file name, which

Printing DHTML (CSS) in Netscape 4.0+

Question: I’ve put together an intranet site that uses JavaScript functions that put together a page. For example, the header section, body section, footer section, sidebar, and so on are

Debugging With the Java Object’s toString() Method

Java’s Object class provides a method called toString() that returns the string representation of the object on which it is called. The method signature for toString() is: public String toString

Interface

Question: What’s an interface in Java programming? Answer: Conceptually, an interface is a class that defines a set of methods with no implementation. It is analagous to a pure virtual

Variable Declaration

Question: I understand that Java variables can be declared public, private, or protected using a similar syntax as C/C++ where the access modifier is placed before the column of variables.