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Creating Radio Buttons Using the AWT

The way you create a set of radio buttons is significantly different between Swing and the AWT. With Swing, you instantiate the buttons and add them to a group object

Creating Radio Buttons Using Swing

Radio buttons behave in the same mutually exclusive way in Swing and the AWT. However, the way that you create a set of radio buttons differs significantly between Swing and

Creating Hidden Buttons with Swing

Using Swing, you can easily create hidden buttons similar to the Back button used in Netscape Communicator 4. Hidden buttons look like normal graphic elements on the screen until you

Infrastructure Functions Should Trust Their Users

Infrastructure functions that are used extensively should adopt the “trust the programmer” policy by not performing additional error checking. This policy is widely used in C/C++ standard libraries. For example,

An Object Size May Never Be Zero

An empty class doesn’t have any data members or member functions. You’d think that the size of an object of such a class would be zero. However, the Standard states

Koenig Lookup

Andrew Koenig devised an algorithm for resolving namespace members’ lookup. This algorithm is used in all standard-conforming compilers to handle cases like the following: namespace MINE { class C {};

Wide Character Literals

A string literal is a sequence of one or more characters enclosed in double quotes: cout

Close All Open Recordsets and Databases

This small subroutine iterates through and closes all databases in the Databases collection of the Workspaces object. For each database in the collection, it iterates through each Recordset and closes

Return to a Previous Location in Your Code

To return to a previous location in your code, press Ctrl+Shift+F2. This way you don’t need to set bookmarks. VB only keeps track of the last eight lines of code

A Fast Way to Find Routines

To quickly go to the code for a called function, subroutine, or property, simply place your cursor on the called routine and hit Shift+F2. VB will immediately go to the

Cancel a Pending Print Job

In the tip, “Please Stop Printing!” [“101 Tech Tips for VB Developers,” Supplement to the August 1997 issue of VBPJ, page 13], the code works fine with one exception. If

Clean Dried Marks on Your White Board

If old words or marks have dried on a white board and you can’t wipe them off, write on top of them with a fresh pen and then rub them

Export SQL Data to a Comma-Separated Value File

Use this code to create a comma-separated value (CSV) file from a recordset based on a SQL query. A number of applications, including Excel and Access, can read CSV files:

C/C++ Linking

Question: If I make a C++ library and supply it to a clientwho does not have a C++ compiler, can theycall my C++ functions from their C routines?That is, is

int and class defination

Question: Why is int 2 bytes with real mode compilers, but 4 bytes with protected mode compilers? And why is the class defination ended with ;-mark, since other definations aren’t?

Windows sound programming.

Question: When writing a Windows 95 program using VC++, how do you play a MIDI sound file? Answer: Musical Instrument Digital Interface (MIDI) is a standard used by electronic keyboards

Terminate and Stay Resident Programs

Question: Can you supply me with boilerplate code for a simple console tsr program? I’m using VC++ 4.0, and I want to create a console program to check a directory

Static initialization and free store

Question: Is it valid to attempt to allocate (via ‘new()’) dynamic memory prior to ‘main()’? I am working on software that has static *’s to class objects, and through some

Making a file circular

Question: I want to make a log file circular using C++ I/O manipulation. I am new to C++ and come from a C background. To me stream I/O is completely

Right shift

Question: Can you tell me how to write a program that right-shifts an integer variable 4 bits? The program should print the integer in bits before and after the shift

Difference between C++ and HTML

Question: What are the main differences between C++ and HTML? If I can use HTML, how hard will it be for me to use C++? Answer: For the most part,

Determining if a ToElement Exists

Question: In a VBScript function I assign the window.event.ToElement to an object for some functionality. The problem is that if the mouse is moved outside of the browser window, the

Selecting and Moving Parts of a String

Question: I have two TField400s. The first TField400 contains the value “12345678” and other TField400 contains the value “11111111”. I want to move the “5678” from the first TField400 and

Event Handling for Dynamically Added Objects

Question: I have used InsertAdjacentHTML to insert a dynamic number of images onto a page in Internet Explorer 4. Having given the new images a single ID, I can refer

Dynamically Change Another Opened Window

Question: I am having trouble creating a site where customers can click something in a parent window and have a picture appear in another child window. I then want customers

Single Quote Marks in a SQL Query

Question: I have built several pages that use VBScript to pull information from a Microsoft Access database. My problem is that if a user tries to use a single quote