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Avoid Redundant Inline Declarations

Remember that functions defined inside the class definition are implicitly inline. Therefore, the inline keyword is redundant in the definition of the member function of the following class: class Employee{public:

Copying Files with File Streams

To copy the contents of one file into another, use the fstream classes. First, open the source file using an ifstream object, then create a target file using ofstream, and

Making Better Use of Garbage Collector

Imagine you have an enormous object serialized on disk that you are using in memory, or that object is loaded in memory. You want to allow the garbage collector (GC)

Implementing Callback Routines

One of the easier ways of implementing an event-driven programming model is through passing function pointers which are invoked when an event occurs. But because Java doesn’t support the notion

Controlling Debugging Information

Debugging is a core part of application development in Java. Programmers tend to use System.out.println & System.err.println in the code everywhere, which becomes uncontrolled as the program evolves. This becomes

Getting Around a Bug in Testing Your Applets

If you’ve tried using the Java Plugin to test your Applets and got a mysterious “Security Exception,” then you’ve run into a known, but unadvertised bug. For a complete description

Checking for Value “NaN”

Question: Why does my if statement if (final == “NaN”) { window.alert(“You…are…a…dunce. Hit reload to try again.”);} fail to detect when final is “NaN”? It always goes straight on to

Date Conversion from Seconds to Normal

Question: Is there some way to write a function that converts a date that is in seconds since December 31, 1969, into a normal date format? Like this: date from

WAP Security Issue

Question: When encrypted information is being interchanged between a client and a “secure” server through WAP, does the information ever lie decrypted on the WAP gateway or does the client

SQL with Unix Arguments

Question: How do I pass arguments from a Unix shell onto SQL for various SQL statements (e.g., select * from $tablename, create table $TABS, etc.)? Also, how do I get

Disabling Right Clicker on Mouse

Question: Is it possible to disable the user’s right click button using JavaScript? Answer: Is it possible? Yes. Oh, you wanted to know how to do it… Keep in mind,

Placing Child Window

Question: How do I make a child window go behind its parent window when a button is clicked? I know self.focus() brings a window forward. I need the opposite of

Blocking E-mail from Specific Address

Question: How do I block an e-mail address from sending messages to our server? A former employee keeps sending messages from his outside account to our current employees. I have

Focusing on Field

Question: I am using onblur method on text fields. Based on Validation I want to put the focus back on field. function fldfocus(fldname) {if (navigator.appName==”Netscape”) {document.Layers[fldname].Focus();else {document.all[fldname].focus();}} On Netscape it

Derive from STL Map<>

Question: I created my own map class (called it Mapper) by creating a template class and deriving from STL map container class. I did so because I wanted to have

Inheritance in C++

Question: In order to have better maintainability and optimum performance, how many levels of inheritance do you recommend ? Answer: Performance is not affected by the depth of inheritance. The

Form with One Text Field

Question: I see search pages that allow text input, then pressing the ENTER key is the same as pressing a link or pushbutton. How is this done? Answer: If a

When Not to Use Query Strings

You should not use query strings when you are passing hidden information and when you are passing large chunks of data. A query string is not hidden in any way

The MB MouseHelper Control

This ActiveX gives you the complete control over the mouse. The MouseEnter and MouseLeave events tell you when the mouse cursor enters or leaves any control on the form, which

GetObjectGUID – Retrieve the GUID of a COM object

‘ Return the GUID of the object specified in the first parameter’ Be sure that “TypeLib Information” type library (TlbInf32.tlb)’ is referenced in your VB project.Function GetObjectGUID(Object As Object) As

GetProcID – Retrieve the DispID of a procedure

‘ Return the DispID of a procedure’ ProcName must be set to a procedure name of the object’ specified in the second parameter.’ Be sure that “TypeLib Information” type library

Layout Manager for Scrolling DIV’s

A scrolling DIV is a great way to display a large amount of data without resorting to frames. Setting the CSS-2 OVERFLOW property to auto will make the DIV into

Avoiding Confusion about an Import Statement

Every source file in Java (.java file) contains one class. You can bundle a set of related classes into a package. Java provides “import” keyword, which is used to establish