An empty # sign is a null preprocessor directive. A null directive has no effect but you can use it to document your intentions, for example: ifndef HEADER_INCLUDED#define HEADER_INCLUDED#else# //

The library supports two types of file streams: char-based streams such as std::ifstream and whcar_t streams. The names of wchar_t streams are the same as their char-based counterparts, except that

Just like the fseek() function of , classes enable you to position the stream’s pointer at an arbitrary location by calling the seekg() member function. For example, you can position

C++ forbids direct assignments of arrays. Therefore, your compiler will flag the following code as an error: char buff[];buff=

Here a few guidelines for improving std::string’s performance and avoiding common pitfalls. Consider the following for-loop: std::string str =

C++ never passes arrays to a function. Instead, the argument is implicitly converted to a pointer that contains the address of the first array element. For example: void f(char s[]);int

An ordinary class may have template member functions. In the following example, the class A declares a template member function called f(): class A{public: template T f(T t);}; You may

The terms template argument and template parameter do not mean the same thing. A template parameter is a symbol, or a placeholder which is replaced by the actual argument when

Many Windows programmers use DLLs abundantly. Although dynamic linking certainly offers some advantages, it can also cause noticeable maintenance and performance setbacks. For starters, DLLs are slower than statically linked

A common myth among programmers says that you can avoid calling delete in your application because the operating system will release the allocated memory when the application terminates anyways. Indeed,

‘ search for a string starting at a given index’ and return the index of the character that follows’ the searched string (case insensitive search)Function InstrAfter(Source As String, Search As

‘ convert a telephone string into a phone numberFunction PhoneNumberFromString(ByVal PhoneString As String) As String Dim i As Integer Dim acode As Integer Const PhoneDigits = “22233344455566677778889999” ‘ prepare result

Here’s a short code snippet that lets you programmatically open and close the CD door. Note that not all the CD drives support these functions: Private Declare Function mciSendString Lib

‘————————————————-‘ LINKED LIST class module” This class implements a linked list structure, where you can store’ values (appending them after the last element or inserting them at’ given indexes), remove

‘ ————————————————————————‘ The CBITARRAY class” simiulates an array of Boolean values’ saves memory by packing one element in one bit” IMPORTANT: you make make ITEM the default member for this

‘————————————————–” The CQUEUE class’ Dim qu As New CQueue” ‘ enqueue to items to the queue’ qu.Enqueue 1234′ qu.Enqueue 5678′ ‘ display number of elements in the queue’ Debug.Print “Count

‘————————————————–” The CSTACK class” Usage:’ Dim st As New CStack” ‘ push two values on the stack’ st.Push 1234′ st.Push 4567′ ‘ display number of elements in the stack’ Debug.Print

‘———————————————-‘ HASHTABLE class module” This class implements a hashtable, a structure that offers many’ of the features of a collectior or dictionary, and is often’ even faster than the built-in

When using a variable as a loop index, it is common to use single-letter variable names. This is a bad practice, because it can make it difficult to find all

Creating controls in Palm OS is very useful. It gives vital power to the programmer in creating applications. There are various controls in Palm OS like buttons, check boxes, radio

There are two ways in SQL Server to execute a T-SQL statement that has been dynamically built. The most common one is using EXECUTE to run it: EXECUTE @sqlstatement In

Selecting the top N rows in a table is no problem in SQL Server, but how to select the 2N to 3N rows is not as clear. Using the following

Here is sample code: import java.security.SecureRandom;public class UniqueNumberGenerator{ static final SecureRandom random = new SecureRandom(); static final StringBuffer buffer = new StringBuffer(30); static { random.nextInt(); } public static String getNextUID()

It seems common knowledge that I/O streams and JDBC database connections are resources that need to be released as soon as they are no longer needed. Not so common knowledge

Many books about JDBC and most of JDBC-related sample code floating around seems to assume that JDBC is used directly, meaning that database connection is established by the DriverManager, and

If you’re like me, and sometimes need to modify Active Directory data from an ASP page where the user is either anonymous, or doesn’t have admin privileges, you need a

The equals() method in the String class is commonly used to compare two strings for equality. However, this method returns true only if the argument is not null and is