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Although the string class is very convenient for most string manipulation operations, it may be necessary sometimes to copy the contents of a string to a different container, e.g., in
If you don’t want users to navigate to another URL when they click on a HTML link in an anchor tag, you need to create a Null HTML link in
Sometimes it’s useful to trap the right click over controls such as CommandButton. Unfortunately, the Click event only fires for left button clicks. The MouseDown and MouseUp events fire for
Prior to VB5, when you wanted to make a form appear on top of another form, you either made it modal or used an MDIForm with children. If you wanted
To prevent losing the ability to maintain binary compatibility with compiled object code, take the first compiled build and move it into a separate directory, then tell VB to maintain
The typical method of validating multiple expressions is to string together a series of If statements separated with an equal number of And statements. Shorten that process by passing one
If you need to get a Web page visitor’s IP address in your ASP script, it
Variables and objects defined within a namespace have static storage type. As such, namespace members are by default initialized to binary zeros before program’s outset. Likewise, namespace members are destroyed
In JavaScript, it is easy to ask the user to confirm an action by using JavaScript Confirm () function. Say you have a function NavigateToWebAddress() (which needs confirmation from the
You can allocate a multi-dimensional array dynamically, as in this example: int*pp[10]; //an array of ten pointers for (int j=0; j
To print the entire document from JavaScript, use parent.print() in the code. For example, this code snippet can be used to print the entire document on click event.
A pure function should never be invoked. However, a buggy program or a buggy compiler can sometimes call a pure virtual function. In general, when a pure virtual function is
There are many ways you can code to create a back link. One of the quick and easy ways to do this is with JavaScript history object. The code snippet
If you set a form’s KeyPreview property to True, all keystrokes for items on that form first trigger the form’s events. This makes it easy to do form-level filtering and
Sometimes you might find it important to know where your site visitors came from. You can then customize your ASP in a certain way, or you know how much your
The communication between the COM client and server can happen in three ways: the vtble interface, dispinterface, or dual interface. The COM client can communicate with the server through IDispatch
In Visual InterDev, you can have more than one view (Project Explorer, Properties, Data, Script Outline, Output, Find, Toolbox, etc) in a docked window. If you have too many of
For an in-proc COM component, a vtbl interface is generally in the order of 100 times faster than a dispinterface (although it depends on type of arguments in the function).
To use the ADO constants, you’ve probably added this piece of code to each of your ASPs: If you write reusable data access ASP code, you might have seen the
The COM client and server can communicate with each other in three ways – vtbleinterfaces, dispinterface or dual interface. If the component is to be used only from compiled languages
When you declare a class as final, it can no longer be subclassed. Java has used this for security purposes with classes like String and Integer. It also allows the
An interface describes the public methods that a class should implement along with the calling conventions of those methods. An Interface says nothing about implementation of its methods. In essence,
When you declare a class as abstract, it cannot be instantiated. Only subclasses of an abstract class can be instantiated if they are not abstract themselves. When you declare a
When you synchronize a method of a class, as in: public synchronized int getAge(){ …} that method will acquire a monitor lock before execution. If the synchronized method is static,
When you declare a field variable of a class as static, that field variable is instantiated only once, no matter how many instances of the class are created. In other
Question: What is the best source, print or online, for learning how to implement persistence in C++? I want to save my objects to disk and restore them, and I
Question: I am using SQL Server 6.5 for my database needs and Visual C++ as a front-end. The problem is that sometimes when I switch on the server (where the
Question: Can I use ADO-connected recordsets with MTS? From the information I can find it seems that MTS does not handle them. Answer: You can, but the question is, do
Question: How does Spy++ make the borders of a window blink when you select “Highlight” from the right-click menu? I have a MouseProc in the hook chain, so I can
Question: I am a young programmer trying to learn C++. I have finished the three books that I own, but none of them cover queues or stacks. I have searched


