VB Mathematical Functions

Mathematical functions are very useful and important in programming because very often we need to deal with mathematical concepts in programming such as chance and probability, variables, mathematical logics, arithematic calculations, coordinates system, time intervals and more. Some of the common mathematical functions in Visual Basic are Rnd, Sqr, Int, Abs, Exp, Log, Sin, Cos, Tan , Atn, Fix and Round. 

For example, Rnd is very useful when we deal with the concept of chance and probability. The Rnd function returns a random number between 0 and 1. In Example 1.

The use of Option Exlicit in VB program

The use of Option Explicit is to help us to track errors in the usage of variable names within a VB program code. For example, if we commit a typo, Visual Basic will pop up an error message “variable not defined”. Indeed, Option Explicit forces the programmer to declare all the variables using the Dim keyword. It is a good practice to use Option Explicit because it will prevent us from using incorrect variable names due to typing errors, especially when the program gets longer. With the usage of Option Explicit, it will save our time in debugging our programs. For example, In the following program, a typo was committed, EmployeID, which was declared as EmployeeID.

Option Explicit
Private Sub Command1_Click()
Dim EmployeeID As String
EmployeID = "John"
Text1.Text = EmployeeID
End Sub 

When you run the program, a dialog box with an error message 'Variable not defined" will appear ,when you click the OK button, it will show the highlighted typo, enabling us to correct the mistake.

Adding Menus to Your VB Application

Most windows programs provide menu bar for easy navigation and control. The most common items are like File, Edit, View, Tools, Help and more. Each item on the main menu bar also provide a list of options in the form of a pull-down menu. 

Adding menu bar is easily accomplished in Visual Basic. To start adding menu items to your application, open your file and then click on Tools in the menu bar of the Visual Basic IDE, then select Menu Editor. When you click on the Menu Editor, the following window will appear. In the Menu Editor, key in the items such as File, Edit, View and etc

Creating a Calender in VB6

Creating a calender in VB6 is a relatively simple task. There is no need to write your own code. What you do is insert the calender component of an ActiveX Control that comes with VB6 into the form. However, the ActiveX control is not included into the toolbox by default, you have to add it with the following steps:

1. From the Project menu, choose Components
2. In the Components dialog, select Microsoft Windows Common Controls 2-6.0 and click OK.
The Calender control will be added to the toolbox. 

3. Select the MonthView control icon from the Visual Basic ToolBox 

4. Drag the MonthView control into the form. 

Now run the program and there you have your very own calender!

 

There is another way to create a calender in VB. This time you use the Microsoft Calender Control 11. As this is also an ActiveX control, it is not launched into the toolbox by default, you need to add it in using the method similar to the above example.
1. From the Project menu, choose Components
2. In the Components dialog, select Microsoft Calender Control 11 and click OK.
Now the calender control will appear in the toolbox. Drag it into the form and press F5 to run the program, and you have your calender as shown below:

 

Try them out yourself. Everyone can do it!