Depending on the version of Windows targeted, there are two different ways to run a VB application during the boot process.Under Windows 9x systems, place a Shell command in the

Private Declare Function LogonUser Lib “Advapi32” Alias “LogonUserA” (ByVal _ lpszUserName As String, ByVal lpszDomain As String, _ ByVal lpszPassword As String, ByVal dwLogonType As Long, _ ByVal dwLogonProvider As

Encapsulation is a fundamental principle in object orientation. Encapsulation restricts direct access to a data member of a class. Instead, users query the object itself in order to get or

Look at the following program. It compiles correctly under every standard-conforming compiler. At first, this may seem surprising because seemingly, because it’s impossible delete an object which is not a

The auto_ptr class template respects polymorphism and destroys derived objects of base pointers properly. In the following program, an auto_ptr is actually bound to a B * pointer, where B

A function call such as the following: classname::funcname(); is a qualified call. Qualified disambiguate function names. They are needed, for instance, in a class that inherits from several base classes,

Here’s a very common error. You define a class but forgot to add a semicolon after the closing }. For example: class Mylist{public: Mylist(); ~Mylist(); //..more member functions} // missing

Because static class members are not associated with a particular object of their class, you can access them even if you haven’t instantiated any object. In the following example, the

The escape sequence ‘a’ is the ASCII code for a beep. To emit a beep from your program, output this escape sequence to the standard output. For example: const char

C++ defines four possible forms for a class’s copy constructor. For a class called X, a copy constructor can have one of the following forms: X(X&);X(const X&);X(volatile X&);X(const volatile X&);

Technically speaking, constructors have no name. This may seem strange at first because you define a constructor for class X as X::X(). However, this construct is not the name of

A reader asked me the following questions: “Can a function that returns something, throw a exception and still return a value?” Lets’ look at a concrete example: int f(){ if

‘ evaluate the transposed matrix” a transposed matrix is the array you get when’ you “rotate” a bi-dimensional arrayFunction TransposeMatrix(arr() As Double) As Double() Dim startRow As Long, startCol As

Option Explicit’ Evalutate the 16-bit CRC (Cyclic Redundancy Checksum) of an array of bytes” If you omit the second argument, the entire array is consideredFunction Crc16(cp() As Byte, Optional ByVal

‘ VBA’s intrinsic Rnd function returns numbers evenly’ distributed between 0 and 1. Each number in that’ interval has equal probability of being returned’ for any given function call.’ This

‘ Converts a decimal value into fractional parts as integers’ (based on the concept of Continued Fractions)’ Examples of usage:’ Call DeclToFrac(0.125, a, b) ‘ 1 and 8 are returned

The following technique will allow you to free your tablespaces from Oracle

In Visual Basic, it is not possible to measure time with more precision than one second. This code allows the user to measure time passed in increments less than one

The method shown below returns as a String the complete path to the current (working) directory. This can be useful to know because default files(including property files) are read from

Private Declare Sub keybd_event Lib “user32” (ByVal bVk As Byte, _ ByVal bScan As Byte, ByVal dwFlags As Long, ByVal dwExtraInfo As Long)Private Const VK_LWIN = &H5BPrivate Const KEYEVENTF_KEYUP =

Like many high-level, abstract, and portable concepts, EJB spec has itsdownsides. One of them is the very generality that makes beans so portable.Interfaces javax.ejb.EntityBean and javax.ejb.SessionBean declare quite a few

In the coming Visual Studio 7, it is possible to create constructors in VB. One of the great benefits of using constructors is that they make it possible to control

When you pass a read-writable property directly as a ByRef parameter to a function or subroutine, the property will not be changed. This is because in VB 6.0 or previous

Trying to pass an ActiveX control as a parameter to a method on an external ActiveX DLL (or EXE), garners a

The duration of a timed task in seconds can be determined by the DateDiff function. To present the result in a user friendly format, pass the DateDiff result to this