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Visual Basic development environment

Given below are the necessary steps to create a Visual Basic program. Programmers call these steps as ‘development cycle’.

• Decide what you want the computer to do.
• Decide how you want your program to look on the screen. (The appearance of your program is called the user interface).
• Draw your user interface by using common components, such as windows menus and command buttons. (The components of user interface are called objects or controls).
• Define the name, color, size and appearance of each user interface object. (An object’s characteristics are called properties.)
• Write instructions in BASIC to make each part of your program do something. (BASIC instructions are called commands).
• Run your program to see whether it works.
• Fix any errors (or bugs) in your program.

Develop an Attractive User Interface

The user interface is what someone sees when your program is running. Every program has a user interface in one form or another. Some programs have elaborate, colorful windows while other programs have a simple appearance.

A VisualBasic user interface consists of forms and objects. A form is nothing more than a window that appears on the screen. Most VisualBasic programs have at least one form, although most programs use several forms.

Objects are items that appear on a form, such as a command button, scroll bar, option button or check box. An object enables the user to give commands to your program.

Define Properties

After you create a form and draw some objects on the form, the next step is to define the properties of each form and object. An object’s properties determine the object’s name, color, size, location and appearance on the screen.

Different object’s have different properties. Each time you draw an object on a form, VisualBasic assigns default property values, which define a generic object that nobody, can really use. If you want to customize an object, you need to define one or more properties for each object used by your program.

Write the code

The final step involves writing BASIC commands (also known as code) to make your program actually work. If you want to edit the appearance of your user interface, you can go back and alter it at any time.

The whole purpose of VisualBasic code is to tell the object on form what to do when the user does something. For example, If the user clicks on an OK or Cancel command button, nothing happens unless you have written BASIC commands to tell your computer exactly what to do.

Any time a user presses a key, moves the mouse, or clicks the mouse button, such an action is called an event. Whenever an event occurs, the code written for that event gets executed (sometime referred as ‘fired’).

Essentially, writing a VisualBasic program means drawing your user interface and then writing BASIC code or procedures to make the user interface work.

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A built-in function is simply a prepackaged price of code that accomplishes a single task. Most of these function put into VB in order to let we to transform sow data into the format hat we need. For example, there are functions that let you take strings apart as well as ones that put them together. The string functions (as the name itself indicates) are those functions, which perform the desired action on the character strings. These character strings known as the arguments of the function can be enclosed in the parentheses () following the function name. Following table gives the string functions in Visual Basic.

Some examples of built-in functions are

• String function
• InStr function
• StrComp function
• Rnd function
• Date function

The need of built-in String functions: String function is used for taking string type variables. E.g. “ This is Visual Basic”.