VB.NET User Interface interview questions and answers
1.You are creating an application
for a major bank. The application should integrate seamlessly with Microsoft
Office XP, be easy to learn, and instill a sense of corporate pride in the
users. Name two ways you might approach these goals in the user interface.
Design the user interface to mimic
the look and feel of Microsoft Office XP, which will allow users of Office XP
to immediately feel comfortable with the new application. Integration of the
corporate logo and other visual elements associated with the company will aid
in identification of the program with the company.
2.You are writing an application
that needs to display a common set of controls on several different forms. What
is the fastest way to approach this problem?
Create a single form that
incorporates the common controls, and use visual inheritance to create derived
forms.
3.If you wanted to prompt a user for
input every time a form received the focus, what would be the best strategy for
implementing this functionality?
Write an event handler for the
Activated event that implements the relevant functionality.
4.Describe two ways to set the tab
order of controls on your form.
You can set the tab order in
Visual Studio by choosing Tab Index from the View menu and clicking each
control in the order you desire. Alternatively, you can set the TabIndex
property either in code or in the Properties window.
5.What is an extender provider, and
what does one do?
Extender providers are components
that provide additional properties to controls on a form. Examples include the
ErrorProvider, HelpProvider, and ToolTip components. They can be used to
provide additional information about particular controls to the user in the
user interface.
6.Explain when you might implement a
shortcut menu instead of a main menu.
If every possible option is
exposed on a main menu, the menu can become busy and hard to use. Shortcut
menus allow less frequently used options to be exposed only in situations where
they are likely to be used.
7.Describe what is meant by
field-level validation and form-level validation.
Field-level validation is the
process of validating each individual field as it is entered into a form.
Form-level validation describes the process of validating all of the data on a
form before submitting the form.
8.Describe how to retrieve the ASCII
key code from a keystroke. How would you retrieve key combinations for
non-ASCII keys?
Keystrokes can be intercepted by
handling the KeyPress and KeyDown events. Both of these events relay information
to their handling methods in the form of their EventArgs. The
KeyPressEventArgs, relayed by the Key-Press event, exposes the ASCII value of
the key pressed in the KeyPressEventArgs. KeyChar property. The KeyEventArgs,
relayed by the KeyDown event, exposes properties that indicate whether
non-ASCII keys such as ALT, CTRL, or Shift have been pressed. To retrieve the
ASCII key code from a keystroke, you would handle the KeyPress event and get
that information from the KeyPressEventArgs.KeyChar property. To retrieve
non-ASCII information, you would handle the KeyDown event and use the
properties exposed by the KeyEventArgs instance.
9.Describe in general terms how to
add a control to a form at run time.
You must first declare and
instantiate a new instance of the control. Then, you must add the control to
the form's Controls collection. Once the control has been added to the Controls
collection, you must manually set properties that govern the control's position
and appearance.
10.What is container
controls ?
Controls that can host other
controls. Examples include Forms, Panels, and TabPages.
11.What is docking?
In Windows Forms, attaching a
control to the edge of the form. You can dock a control by setting the Dock property.
12.What is Access Keys?
Access keys allow users to open a menu by
pressing the Alt key and typing a designated letter. When the menu is open, you
can select a menu command by pressing the Alt key and the correct access key.
For example, in most programs, the Alt+F key opens the File menu. Access keys
are displayed on the form as an underlined letter on the menu items.
13.What is Shortcut keys?
Shortcut keys enable instant
access to menu commands, thus providing a keyboard shortcut for frequently used
menu commands. Shortcut key assignments can be single keys, such as Delete, F1,
or Insert, or they can be key combinations, such as Ctrl+A, Ctrl+F1, or
Ctrl+Shift+X. When a shortcut key is designated for a menu item, it is shown to
the right of the menu item.
14.What is Context menus?
Context menus are menus that
appear when an item is right-clicked. Context menus are created with the ContextMenu component.
15.Briefly describe the three types
of user-developed controls and how they differ.
The three types of user-developed
controls are inherited controls, user controls, and custom controls. An
inherited control derives from a standard Windows Forms control and inherits
the look, feel, and functionality of that control. User controls allow you to
combine standard Windows Forms controls and bind them together with common
functionality. Custom controls inherit from Control and are the most
development-intensive kind of control. Custom controls must implement all their
own code for painting and inherit only generic control functionality. All
specific functionality must be implemented by the developer.
16.Describe the roles of Graphics,
Brush, Pen, and GraphicsPath objects in graphics rendering.
The Graphics object represents a
drawing surface and encapsulates methods that allow graphics to be rendered to
that surface. A Brush is an object that is used to fill solid shapes, and a Pen
is used to render lines. A GraphicsPath object represents a complex shape that
can be rendered by a Graphics object.
17.Describe the general procedure for
rendering text to a drawing surface.
You must first obtain a reference
to a Graphics object. Next, create an instance of a GraphicsPath object. Use
the GraphicsPath.AddString method to add text to the GraphicsPath. Then, call
the Graphics.DrawPath or Graphics.FillPath to render the text.
18.Describe the role of the
LicenseProvider in control licensing.
The LicenseProvider controls
license validation and grants run-time licenses to validly licensed components.
The LicenseManager.Validate method checks for an available license file and
checks against the validation logic provided by the specific implementation of
LicenseProvider. You specify which LicenseProvider to use by applying the
LicenseProviderAttribute.
19.Describe how to create a form or
control with a nonrectangular shape.
Set the Region property of the
form or control to a Region object that contains the irregular shape. You can
create a Region object from a GraphicsPath object.
