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The Latest

Another Way of Handling Null Database Fields

A compact way of handling null database fields is as follows: txtText1.text = Format(rs!Field) If rs!Field is null, Format(rs!Field) will resolve to an empty string.Otherwise the value in the recordset

Handling Dialogs With One Line of Code

Handle dialogs with one line of code by encapsulating the show method within the form in a public function. This makes the form/dialog reusable and simpler to implement and update.

View Recordsets in Temporary Grids

An alternate, convenient way to view recordsets in debug mode is to persist a recordset to disk using rs.save MyFileUNC.ADTG in the immediate window. Note that the file must be

A Powerful and Simple Message Box Statement

This tip can be used as a Select Case statement with a MsgBox statement. Because a variable is not used to hold the response, adding one or more handles for

Adding Popup Menus to Custom Controls

Shipping custom controls with their own set of popup menu items make the controls appear appropriately professional. They add ease of use, functionality and value to the control(s). Here’s how

Adding Items in List Boxes as Tooltips

This piece of code lets you display an item in a list box as that list box’s tooltip. Private Sub lstItems_MouseMove(Button As Integer, Shift As Integer, X As Single, Y

Correct Authentication Flags in ADSI and VB

If you are unsuccessful at attempting to bind to an object residing in a Netscape Directory Server and you are using ADSI in VB or VBscript, you are likely using

Making a Form Scrollable

This is one of the simplest, but most powerful, ways to make a form scrollable. This method automatically disables or enables scrollbars according to the size of the area in

Cut, Copy, Paste, and Undo For Textboxes

Many programmers use Visual Basic’s Clipboard object to perform Cutting, Copying, Pasting and Undoing code. For example, to copy some text from a textbox, programmers sometimes use the following code:

Using a Boolean Expression to Group Records

Sometimes there is a need to group records into two larger categories, regardless of all other groupings. Using the Northwind database for an example, let

CTreeViewEdit – A class for enhanced treeview node editing

‘——————————————————-‘ The CTREEVIEWEDIT Class module” This class lets you use a regular TextBox control to’ edit a treeview node’s label. All you have to do to’ use this class is

Determine Absolute Row Index

Often, properties and methods associated with grid controls don’t provide an absolute (relative to the actual first row and not the first displayed row) row index of current or selected

The #error Preprocessor Directive

During the preprocessing phase, you can report errors by using the #error preprocessor directive. For example, suppose you have a program that uses 64-bit integers. This program has to be

<iostream.h> or <iostream>?

Although the library was deprecated for several years, many C++ users still use it in new code instead of using the newer, standard compliant library. What are the differences between

Generating Random Float Values

To generate random floating numbers, choose a floating point number, divide it by the largest value of int type and multiply the result by the value of a function that

Using const Variables to Define the Size of an Array

C++ requires that the size of an array be a constant integral expression. However, the following code refuses to compile: // in const.hextern const int ID_LENGTH; // declaration// in const.cppconst

Controlling Floating Point Precision

You can override the default number of digits after the decimal point by calling the precision() member function of an ostream object. The following program first displays six digits after

std::vector Iterators

To create an iterator of a vector, you have to use a vector specialization. In the following examples, I create two vector iterators: one for the specialization vector and another

Octal and Hexadecimal Output

By default, cout displays integral values as decimal numbers. You can override this setting and have integral values displayed in hexadecimal and octal notations by using the ‘hex’ and ‘oct’

Casting To and From void*

In C++, pointers are strongly-typed. Therefore, you can’t assign a void pointer to any other pointer type without casting it explicitly: int n;void *p = &n;int *pi=static_cast< int* >(p);//C++ requires

Null Pointers and Delete

C++ guarantees that operator delete checks its argument for null-ness. If the argument is 0, the delete expression has no effect. In other words, deleting a null pointer is a

Switching Between Fixed and Scientific Notation

By default, iostream objects are set to display floating point values in fixed notation. To change this, you apply the ‘scientific’ manipulator to an output stream object: #include using namespace

Simplifying Date Data Entry, Part III

f you have been following this series of articles, you know the problems with date data entry and the proposed a pop-up calendar solution that allows a user to pick

Profiling in Oracle 8i

n a previous 10-Minute Solution, “New PL/SQL Features in Oracle 8i: Part I,” I write that Oracle PL/SQL programmers develop complex code nowadays, utilizing custom and Oracle-supplied packages. It therefore

Creating a “Complete” Backup Solution

ne of the inherent difficulties in backup and contingency planning is that it usually takes only one thing to go wrong to bring down your entire system. To be truly