GUI Controls and Properties Overview

Controls

• Controls are graphical user interface (GUI) elements used in forms.
• They act as visual widgets for user interaction.
• Controls manipulate other objects in the backend, like database control and timer control.
• You can change a control’s properties by editing them in the Properties window.

Properties Window

• The Properties Window allows you to view a control's properties.
• Properties can be organized by category or alphabetically.
• Clicking the lightning bolt button lets you view events associated with a control.

Control Prefixes

• It's recommended to use 3-letter lowercase prefixes for controls to improve code readability.
• Examples include:
  • Form: frm
  • Button: btn OR cmd
  • Label: lbl
  • TextBox: txt
  • CheckBox: chk
  • RadioButton: opt
  • List control: lst
  • Combo Box: cmb
  • Group Box: grp
  • Panel: pnl
  • Picture Box: pct

Common Control Properties

• Name: Programmatic name of the control.
• Anchor: Determines how a control is resized with its parent container.
• BackColor: Background color of the control.
• BackgroundImage: Background image displayed in the control.
• Dock: Determines how a control is resized with its parent control.
• Enabled: Indicates whether the control can respond to user interaction.
• Font: Font of the displayed text of the control.
• ForeColor: Foreground color of the control.
• Size: Gets or sets the control's size (Height and Width).
• Location: Represents the control's upper-left corner in container coordinates.
• Text: Text associated with the control.
• Visible: Indicates whether the control is shown or hidden.

Form

• The Form is the main container for controls in an application.
• An application can contain multiple forms.

Form Properties

• FlatStyle: Controls the appearance of the button control in flat style.
• FlatAppearance: Defines the appearance of the flat style border and colors.
• Image: Sets the image displayed on the button control.
• ImageAlign: Controls the alignment of the image on the button control.
• TextImageRelation: Determines the position of text relative to the image.

Button Control

• The default event for the Button control is Click.

Text Box

• The TextBox control facilitates user input of text.

Text Box Properties

• BorderStyle: Sets the border type.
• MaxLength: Limits the maximum number of characters that can be entered.
• Multiline: Indicates whether the textbox can accept multiple lines of text.
• PasswordChar: Defines the character used to mask password characters visually.
• ReadOnly: Makes the textbox read-only.
• SelectedText: Provides access to the currently selected text.
• TextAlign: Sets the text alignment within the textbox.

Text Changed Event

• The default event for the TextBox control is TextChanged.

Focus() Method

• Focus() method dynamically places the cursor in a control, allowing for immediate user interaction.
• It is commonly used with the TextBox control.

MessageBox.Show Function

• Displays a message box with customizable text, caption, buttons, and icons.

Parameters

• text: Text to be displayed in the message box.
• caption: Text to be displayed in the message box's title bar.
• buttons: Specifies which buttons to display.
• icon: Sets the icon to display in the message box.

Return Value

• One of the DialogResult values, indicating the user's choice.

MessageBoxButtons Enumeration

• Defines the available buttons to display for the MessageBox.Show function.

MessageBoxIcon Enumeration

• Defines the available icons to display in the message box.

DialogResult Enumeration

• Defines the possible return values from a MessageBox.Show function.

This quiz covers the key concepts of graphical user interface (GUI) controls, their properties, and recommended naming conventions. Learn about the functionality of controls, the usage of the Properties Window, and common properties associated with different control types. Test your knowledge about creating user-friendly interfaces!