A rule of thumb in class design says that if a class has at least one virtual function, it should have a virtual destructor, too. This is because the presence

I have a much simpler form for the IsAlphaNum function: Public Function IsAlphaNum(ByVal sString _As String) As BooleanIf Not sString Like “*[!0-9A-Za-z]*” _Then IsAlphaNum = TrueEnd Function You can modify

Although VB has an IsNumeric function, it has no IsAlpha function. Use this routine whenever you want to determine whether a character or string of characters is alphabetic (A-Z or

This can be done by using ResultSetMetaData. For example, to get the number of columns you can use: /* get the meta-information about the result set */ResultSetMetaData metaData = rs.getMetaData();

Traditional testing for alphabetic characters

Blank finals are fields that are declared as final, but are not given an initialization value. Java allows the creation of blank finals, but, in all cases, the blank final

Sometimes you need to know the number of bits set in a word. I often see code to count the number set bits written as a loop, processing one bit

When you need to add the same member function to several classes, you can use a template class, derived from its template argument. template class T : public P {public:

These days, many enterprises exchange data using a request/response approach. This data typically contains the date and time information regarding when a request was generated/received or a response generated/received. If

In DOM compliant browsers (IE5 & NS6), you can handle attributes of all similar elements with the getElementByTagName() function. For example, to change the background color of all the cells

SQL*Plus uses column names as default column headings while displaying query results. You can customize your own column heading and width with the help of following commands. To assign a

Suppose we have a class called A. A has a data member p which is a pointer to another object: class A{public: A() {p = new B[10];}private: int *p;}; We

Certain applications make use of very long strings. For example, a single string may contain generated HTML pages, a chapter of a book, a textual database and so on. Usually,

Although you can declare an entire class a friend of another class, like this: class A{ friend class B; //B has access to every member of A //..}; However, in

Java containers have a mechanism to prevent more than one process from modifying the contents of a container. The problem occurs if you

When displaying a recordset in a table with a border, if there is no data returned for a cell, the borders will not show up around that cell. To alleviate

Below is an example of passing in parameters when calling a stored procedure from an ASP page.

When you extend a class and override a method, Java insists that the new method cannot be declared as throwing checked exceptions of classes other than those that were declared

When a connection is created using JDBC, by default it is in auto-commit mode. This means that each SQL statement is treated as a transaction and will be automatically committed

Often, while developing a system, you need to put a lot of debug statements in the code, all which have to be commented/removed before delivering the application. There’s a class

When you

You can use the Dir( ) function to return a long filename, but the return does not include path information. By parsing a given short path/filename into its constituent directories,

Don

The Resource Editor add-in is useful for adding resource file text entries, but it doesn

Be aware that VB doesn

Public variables at module level are thread specific. Each new thread starts get a new fresh & uninitialized copy of such variables. All the activities that are born from the

When you decide to release a new version of an MTS/COM+ component you should take care of its compatibility with the previous version. There are three types of changes you

When you deploy COM objects in DLLs no security issues arise since DLLs run in the process of the caller. On the contrary, when you deploy your COM objects into