CSC 3 Week 3
VISUAL BASIC .NET Overview
Course Code: CSC 3
Level: Intermediate Programming
Topics Covered
Forms Control
Properties
Methods
Events
Basic Controls
Forms Control
Definition:
Refers to the core components of a graphical user interface (GUI) application.
A Form is the main container for all controls (e.g., buttons, labels, text boxes) and is the foundation for Windows desktop applications in VB.NET.
Object-Oriented Aspects of Forms
Object-Based Programming:
An object in Visual Basic is a user interface element created using toolbox controls.
The form itself acts as an object.
Control Elements
Properties:
Describe the characteristics of an object.
Methods:
Functions that allow the object to perform actions.
Events:
Actions that occur due to user interactions.
Form Properties
Definition:
Form properties define appearance, behavior, and functionality.
Setting Properties:
Can be set during design time via the Properties window in Visual Studio or at runtime programmatically.
Key Form Properties
No. Property Description | ||
1 | AcceptButton | Automatically activates the specified button on Enter key press. |
2 | CancelButton | Activates the specified button on Esc key press. |
3 | AutoScale | Determines if controls are automatically scaled to font height (default True). |
4 | AutoScroll | Indicates if scroll bars are attached if the form is resized. |
5 | AutoScrollMinSize | Specifies minimum size before scroll bars are attached. |
6 | BackColor | Sets the form's background color. |
7 | BorderStyle | Determines the appearance of the form’s border. |
8 | ControlBox | Determines if the control menu is visible. |
9 | Enabled | Enables/disables the form's response to events. |
10 | Font | Specifies the font of the form. |
11 | Height | Sets the height of the form in pixels. |
12 | MinimizeBox | Hides the minimize button if set to False. |
13 | MaximizeBox | Hides the maximize button if set to False. |
14 | MinimumSize | Specifies the minimum form size when minimized. |
15 | MaximumSize | Specifies the maximum form size when maximized. |
16 | StartPosition | Initial positioning of the form when displayed. |
17 | Text | Text shown in the title bar of the form. |
18 | Width | Sets the width of the form in pixels. |
Form Methods
Definition:
Methods are functions that perform specific actions with a form, controlling its behavior.
Commonly Used Form Methods
Sr.No. Method Description | ||
1 | Activate | Activates the form and gives it focus. |
2 | Close | Closes the form. |
3 | Hide | Conceals the form from the user. |
4 | Show | Displays the form to the user. |
5 | CenterToScreen | Centers the form on the current screen. |
Form Events
Definition:
Events trigger specific actions upon user interactions and changes in the form’s state.
Commonly Used Form Events
Sr.No. Event Description | ||
1 | Activated | Occurs when the form is activated. |
2 | Click | Occurs when the form is clicked. |
3 | Closing | Occurs when the form is about to close. |
4 | Load | Occurs before the form is displayed for the first time. |
5 | Resize | Occurs when the form is resized. |
Basic Controls
Definition:
VB.Net provides diverse controls for creating rich user interfaces, defined in the System.Windows.Forms namespace.
Common Controls
Sr.No. Widget & Description | |
1 | Forms |
2 | TextBox |
3 | Label |
4 | Button |
5 | ListBox |
6 | ComboBox |
7 | RadioButton |
8 | CheckBox |
9 | PictureBox |
10 | ProgressBar |
11 | ScrollBar |
12 | DateTimePicker |
13 | TreeView |
14 | ListView |