It is customary to overload the subscript operator, [], in classes that hold a sequence of elements. Vector and String are examples of such classes. When you overload operator [],

When executing code and tying up the system, developers often use a label or status bar to display messages. If you simply assign your text or message to the control

C code should not access objects that have a virtual base class. The reason is that a virtual base is usually represented in the form of a pointer to a

The fourth restriction on the legality of accessing C++ objects from C code states that all the data members of the class must be declared without an intervening access specifier.

In the case of virtual functions, an additional member is inserted into the class: a pointer to the virtual table, or _vptr. The _vptr holds the address of a static

Be careful about tips to easily duplicate tool-tip help with only tip control and mouse events. If your “tip” control doesn’t have the same parent as the control you’re moving

Jeremy Boschen pointed out an easy way to load a Boolean into a check-box control in the tip, “Use Boolean Variables for Check-Box Values” [101 Tech Tips for VB Developers,

The latest versions of Internet Explorer (4.0 and 5.0) make it easy to add a dramatic drop shadow effect to regular text. Rather than creating bitmaps, try adding a style

Question: Is it possible to insert the single quote as part of a Name like O’Brian into a table using a SQL Insert Statement? Answer: Yes, use double quotes around

Question: Is there an option to set deletion without getting logged? I have to delete two years of historical data but would like to keep this year’s data on my

Question: I’m using MSC/C++ 7.0 to write a program for my Foxpro 2.5. How can I compile it to the Foxpro’s PLB format? Answer: You need the Foxpro LCK (Library

Question: In a SQL Select statement:Is it possible to define ORDER BY (random) Answer: The answer to your question is “no”. The ORDER BY clause must refer to specific fields

Question: How would I drop an index from a table using SQL? Answer: Here is the syntax for the drop index command: DROP INDEX [owner.]table_name.index_name[, [owner.]table_name.index_name…]Ex. DROP INDEX authors.au_id_ind Related

Question: In FPW 2.6 I often get a ‘variable not found’ message when the read statement executes. This usually happens only the first time the screen is used in the

Question: I wanted to find the copy files wait screen (where it shows a file jumping from one folder to another). How can I do this and what is it

Referencing a static local variable in a procedure is 2-3 times slower than a regular local, dynamic variable; if you want to really speed up your procedures, convert all static

Visual Basic doesn’t provide you with a means for creating a Missing value, a feature that in some cases would prove useful in order to simplify the syntax of calls

If your forms contain Label controls used to display data from a database, set their UseMnemonic property to False. In fact, if you leave this property to its default value

When using the ParamArray keyword within a procedure, always remember that when the procedure is invoked from elsewhere in the program one of the argument might be omitted, and you

When working on an updated version of a COM component, you should always enforce Binary Compatibility in the Component tab of the Project Properties dialog box. When enforcing binary compatibility

Private Declare Function ImageList_ReplaceIcon Lib “COMCTL32” (ByVal hImageList _ As Long, ByVal i As Long, ByVal hIcon As Long) As Long’ Load a set of images from a disk file

‘ Save all the images in an ImageList control to a disk file’ Images can be later loaded in the same ImageList control using the’ LoadImageList routine” Note 1: if

It seems that the only way to count the number of 1’s or 0’s in a binary value is creating a loop that iterates on all the 16 or 32

‘ returns the last occurrence of a substring’ The syntax is similar to InStrFunction InstrLast(ByVal Start As Long, Source As String, search As String, _ Optional CompareMethod As VbCompareMethod =

There are a lot of risks involved in using End in VB programs: your databases might not be correctly closed, your objects are not correctly terminated, etc. You should always

Under some circumstances, an ActiveX DLL can pass private objects to its client application, for example a reference to a control that belongs to a form in the DLL. While

You should always modify a vertical scrollbar’s width and a horizontal scrollbar’s height to conform to the display resolution. You can learn the suggested size (in pixels) using the GetSystemMetrics

When testing a component in the IDE, always perform a full compilation. This ensures that VB checks the syntax of all the code in the component, which in turn guarantees

‘ Return True if a directory exists’ (the directory name can also include a trailing backslash)Function DirExists(DirName As String) As Boolean On Error GoTo ErrorHandler ‘ test the directory attribute