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The Latest

Understanding Zero Initialization

To zero-initialize an object of type T means that the memory storage occupied by the object is set to binary zeros. More precisely, if T is a built-in data type,

Rounding a Number Up and Down

The standard &ltmath.h> header declares the function ceil() and floor(). These function round the fractional part of a floating point number. ceil() returns the smallest integer that is no less

Declaring a Volatile Member Function

You’re probably familiar with const member functions such as: class A { public: int get_x() const; // can’t change A’s state }; C++ also supports volatile member functions. You declare

The this Pointer

In the body of a non-static member function, the keyword this is a non-lvalue expression whose value is the address of the object for which the function is called. However,

Find Constant Name

Question: Instead of trapping an Error by its value (If err.number=429 then…) I would prefer to use a VB defined Constant Name.I can’t seem to find a way to locate

Databases and Large Amounts of Data

Question: I wrote a VB program that uses MS-Access (MDB) type data base using DAO . The application gathers a huge amount of information (25meg a week) and accesses the

Setting Reminders

Question: I am developing an application in VB which requires Reminders. On the basis of dates input, if the current date goes past the date in the database it should

Initialization of an Array of Classes

Question: A common practice in C is to do something like this to initialize an array of structs: typedef struct {float x,y,z;} Vector3;Vector3 VecList[] = {{1,0,0},{0,1,0},{0,0,1}};// Now VecList[0] = {1,0,0};//

Assigning C-strings

Question: I am just beginning to learn C++ and I’ve stumble on an error that I cannot figure out despite all my efforts. Here is the code where I’m having

Calling a C Program

Question: I’ve created a console C program that has parameters input on thecommand line and would like to create a Java application that selectsthe parameters and calls the C program

Cascade/Tree Menu

Question: I have an Access database in which I would like to place a tree menu in a form. In this tree menu you would be able to make a

Additem Method Syntax

Question: I am trying to use additem to make an addition during a dragdrop event into a list from a textbox. I tried the code: ListName.AddItem = TextName.TextTextName.Text = “”

Overloading Operator

Question: How do I overload the ++ operator to work with an enum variable? For example, I defined SuitType to be {Heat, Club, Diamond, Spade}. I want to use s++

Disable New and Delete

Question: I’m a team leader, I’d like to disable new and delete, so others can’t call these functions, is there a good way to do it? Answer: You can’t really

Pure Virtual Destructors

Question: I heard someone saying that C++ standardization does not allow pure virtual destructors not to have a definition. As far as I know, this is not true. Could you

Linking a *.c with a *.h File

Question: As a developer new to C (I’m using Borland C/C++ version 5), I am trying to understand the method of linking *.c and *.h files within an application. First

Standalone Executable

Question: How can I compile a Java application’s class files into a standaloneexecutable file without using a commercial native code compiler and atthe same time keep it platform independent? Answer:

Multiple Applications Running On One JVM

Question: I want to know how to run more than one application under one VM. Iam developing some Java servers, but I don’t want 10 JVMs running whenonly one is

Buffered Object Streams and Sockets

Question: How can I use buffered I/O Object streams over a socket and guaranteetransmission even when the packet object is smaller than the buffersize? I want the efficiency benefits of

Copy and Delete Files Using ASP Code

Question: How do I copy files from point A to point B from within my ASP page? After I have used the file that has been transferred to point B,

Use a Where Clause in SQL Instead of a Filter

Question: Here is a snippet of my code: set conn = Server.CreateObject(“ADODB.Connection”)conn.open “gorillaclasses”set rs = Server.CreateObject(“ADODB.Recordset”)stmt = “SELECT class,time,instructor FROM ” & clubtable rs.open clubtable, conn, adOpenStatic,,adCmdTable %>rs.filter = “dayslot

Java Applet Environment

Question: Could you please elaborate on the difference between working in a Javaapplet environment and in a distributed client server environment. Answer: Applets can be used to implement client server

Anonymous Inner Classes

Question: Is it possible for an anonymous inner class to extend a class andimplement an interface, or for it to implement two or more interfaces? Answer: The only way an

EJB Scalability

Question: One of EJB’s obvious design goals was to provide an environment thatcan scale up to meet the demands of enterprise applications. I’mcurious, however, about the other end of the

GetDriveInfo – Drive serial number and other data

Private Declare Function GetVolumeInformation& Lib “kernel32” Alias _ “GetVolumeInformationA” (ByVal lpRootPathName As String, _ ByVal pVolumeNameBuffer As String, ByVal nVolumeNameSize As Long, _ lpVolumeSerialNumber As Long, lpMaximumComponentLength As Long, _

GetFileVersionData – Retrieve file versioning information

Private Declare Function GetFileVersionInfoSize Lib “version.dll” Alias _ “GetFileVersionInfoSizeA” (ByVal lptstrFilename As String, _ lpdwHandle As Long) As LongPrivate Declare Function GetFileVersionInfo Lib “version.dll” Alias _ “GetFileVersionInfoA” (ByVal lptstrFilename As

DriveExists – Check whether a logical drive exists

Private Declare Function GetLogicalDriveStrings Lib “kernel32” Alias _ “GetLogicalDriveStringsA” (ByVal nBufferLength As Long, _ ByVal lpBuffer As String) As Long ‘ Check whether a given drive exist’ Note that this