Deck 10: Programming Based on Events

Question 1

When you define a delegate type,you identify what types of methods the delegate represents.

Answer 1

True

Question 2

Associating a method in your program to an event is called delegating the event.

Answer 2

False

Question 3

Both the ComboBox and ListBox objects inherit members from the Control class.

Answer 3

True

Question 4

Delegates work well in an event-driven arena because the same delegate can call different methods during runtime.

Question 5

ComboBox objects save space on a form through their use of a predefined size property.

Question 6

Like other classes,an instance of a delegate is called an object.

Question 7

The delegate definition does not include a body. All that is included is the heading.

Question 8

The delegate signature indicates what the method signatures must look like if they are to be referenced by the delegate.

Question 9

The Items property can be used to set the initial values for a ListBox object. The Items editor is opened when you click the ellipsis to the right of the Collection property in the Properties window.

Question 10

Since each delegate wraps a single method,there must be a one-to-one correspondence between the method and its delegate.

Question 11

The this keyword is used to indicate the current instance of the delegate.

Question 12

The ListBox control object can hold data of string type only.

Question 13

To add functionality to the ListBox control object,you register the DoubleClick( )event handler method.

Question 14

The declaration for a delegate looks more like a method declaration than a class definition.

Question 15

Multiple selections cannot be made from a ListBox control object.

Question 16

ListBox objects have an added feature in that they contain their own text box field as part of the object.

Question 17

To set the background color for the ListBox control,use the Back property.

Question 18

Use the Format>Align menu options to line up associated controls so controls are consistently placed in the same row or column.

Question 19

The TabControl object displays multiple tabs,like dividers in a notebook or labels in a set of folders in a filing cabinet.

Question 20

The Items,SelectedItems,and SelectedIndices properties are useful for retrieving selected items from the ListBox object.

Question 21

Menus offer the advantage of requiring less real estate on the screen.

Question 22

A test plan to verify the accuracy of the application should be designed before coding the application.

Question 23

One of the advantages of a ListBox object over other types of objects used for input is ____.

A) it can be used for both input and output
B) it can be used for both console and Windows applications
C) an event handler method can be registered
D) multiple selections can be made

Question 24

To wire a method to an event,such as a menu selection,means you associating multiple methods to the event.

Question 25

The process that includes identifying an event,such as a button click as being of interest,and associating a method to be executed when the event occurs describes ____.

A) wiring an event
B) delegating an event
C) balancing an event
D) referencing an event

Question 26

Included as part of .Visual Studio are a number of preconfigured dialog boxes Find and Replace,Spell Checker and File Save.

Question 27

Double-clicking on the ListBox control registers which default event?

A) SelectedIndexChanged
B) Click event
C) DoubleClick
D) ItemChanged

Question 28

Delegate signatures differ from method signatures in that the delegate also includes its ____.

A) name
B) return type
C) number of parameters
D) type of parameters

Question 29

Delegates are special types of .NET classes whose instances store ____.

A) references to actual data.
B) data
C) references to methods
D) methods

Question 30

To add an icon for the application,add a PictureBox object and set the Image property to the desired jpg image.

Question 31

A ____ control offers the advantage of multiple selections and the opportunity to add or remove items dynamically at runtime.

A) Button
B) TextBox
C) ListBox
D) Label

Question 32

An instance of the delegate class is called a(n)____.

A) object
B) instance
C) variable
D) delegate

Question 33

TabControl objects,which are placed on top of button objects,enable multiple tabs to appear on a form.

Question 34

A number of objects can be wired to the same event-handler method.

Question 35

The Form object also has a BackgroundImage property that can be set to display a
picture on the background.Select the form and then use the Properties window to browse to a location that contains the file.

Question 36

Delegate declarations resembles ____ declarations.

A) method
B) variable
C) object
D) data

Question 37

When the delegate wraps more than one method,it is called a(n)____ delegate.

A) multicast
B) multiple
C) multi-referenced
D) multi-event

Question 38

SelectedItems and ____ properties can be used to retrieve items from a ListBox object.

A) Selected
B) SelectedItem
C) Name
D) ListBoxItems

Question 39

A KeyPress( )event is fired with each and every keystroke.

Question 40

The default setting for the ComboBox object's DropDownStyle property,is DropDown.Retaining this setting prohibits new text from being entered into the ComboBox.

Question 41

You can add a shortcut to a menu by preceding one of the characters in the menu name with a(n)____. This places an underline under the next character typed.

A) underscore (_ )
B) hyphen (-)
C) ampersand (&)
D) asterisk (*)

Question 42

The default event-handler method for the ComboBox control is ____.

A) KeyPress( )
B) SelectedIndexChanged( )
C) Click( )
D) Changed( )

Question 43

An added value of ComboBox objects is that compared to a ListBox object they ____.

A) save space on a form
B) enable input and output of data
C) can be used for multiple selections
D) can have events of interest registered

Question 44

What does the following statement do? this.BackColor = System.Drawing.Color.Blue;

A) sets the form color to Blue
B) sets whichever control you have selected to Blue
C) sets all of the controls on the form to Blue
D) sets the drawings on the form to Blue

Question 45

With Windows Presentation Foundation (WPF)applications,____.

A) you see completely different controls available in the toolbox
B) drag and drop is not an option for placing controls on the form
C) less sophisticated multimedia options are available
D) a new XAML file, resembling an HTML file, is added to the solution

Question 46

To retrieve multiple selections from a ListBox control,you can use all of the following properties EXCEPT ____.

A) SelectedItems
B) SelectedIndices
C) Text
D) Items

Question 47

In order for event handlers to be called using delegates,the delegate must ____.

A) be declared with a return type of void
B) include at least two parameter arguments representing the event and object
C) be instantiated in the application as a delegate
D) maintain a list of the registered event handlers for the event

Question 48

One way to convert item objects retrieved from ListBoxes to strings for displaying is to use the Text property for retrieval.Another option is to retrieve the values as objects using the SelectedItem property and invoke the ____________ method.

Question 49

Which of the following is one of the pre-configured dialog boxes that can be added to an application?

A) StyleDialog
B) ViewDialog
C) StyleDialog
D) ColorDialog

Question 50

ComboBox objects have an added feature over the ListBox controls in that ____.

A) ComboBox objects contain their own text box field
B) Scrollbars are included with ComboBox objects
C) ComboBox objects enable multiple selections
D) ComboBox objects can be used for input and output

Question 51

What is the name of the default event handler method for RadioButton and CheckBox objects?

A) Click( )
B) SelectedIndexChanged( )
C) KeyPress( )
D) CheckChanged( )

Question 52

____ objects usually appear as small boxes that allow users to make a yes/no selection.

A) RadioButton
B) ListBox
C) CheckBox
D) ComboBox

Question 53

To retrieve data from a ListBox control as string data,use the ____ property.

A) SelectedItem
B) SelectedItems
C) SelectedIndices
D) Text

Question 54

You change the appearance of the tabs for a TabControl object using the ____ Collection Editor.

A) TabPage
B) Controls
C) Properties
D) Text

Question 55

Which property is used with the PictureBox control to associate an actual picture to the control?

A) Resource
B) Image
C) Icon
D) Picture

Question 56

To create mutually exclusive options use ____.

A) a GroupBox object with RadioButton objects
B) a GroupBox object with CheckBox objects
C) either a RadioButton and CheckBox object
D) a ListBox object

Question 57

The SelectionMode property of the ListBox object ____.

A) enables multiple selections to be made
B) determines whether you can use the mouse or the keyboard
C) sets which of the items is initially selected
D) determines whether use selections can be added

Question 58

With a ListBox of numbers,the SelectedItem property returns ____.

A) the one selected in an int or double format.
B) an object representing the one selected.
C) a string representing the one selected.
D) the index of the one selected.

Question 59

The ____ class in the System.Windows.Forms namespace enables you to add more functionality to your application by offering additional user options,such as adding layers of menus.

A) MenuStrip
B) MenuDialog
C) Main
D) DialogMenu

Question 60

To have the ListBox or ComboBox Items arranged in alphabetical order ____.

A) the values must be originally type in the desired order.
B) use a drag and drop approach move the items into their correct order.
C) set the Sorted property to true.
D) set the Ordered property to ascending or descending.

Question 61

____________ objects have an added feature over a ListBox objects that they contain their own text box field as part of the object,but they allow only a single selection to be made.

Question 62

All event-handler take two parameters.The first parameter,object sender,represents the source that raises the event,and the second parameter is the data for the event;thus,they normally have the same ____________.

Question 63

In order to add values to the ListBox at run time,invoke the Add( )method on the ____________ property.

Question 64

The ListBox ____________ property has selection values of MultiSimple,MultiExtended,None and One.

Question 65

The ____________ event fires when a key is pressed while the control has focus.

Question 66

Objects like colorDialog,fontDialog,ToolTip and MenuStrip are added to the ____________ for the application when they are dragged and dropped onto the form.

Question 67

The ListBox object allows multiple options for retrieving selections.When multiple selections are made,to retrieve all of the selections,the ____________ property cannot be used since it retrieves a single selection,the first one selected.

Question 68

The ____________ method associated with the predefined dialog classes,like FontDialog or ColorDialog causes the dialog box to be displayed.

Question 69

You can assign a(n)____________ to controls,such as text boxes or menu items,so that text is displayed when the cursor is rested on top of the component.

Question 70

A(n)____________ is an underlined character in the text of an menu item or on the label of a control such as a button that enables user to click the button,without using the mouse,by pressing the Alt key in combination with the predefined character.

Question 71

To add functionality to a control such as a Button or ListBox,you need to ____________ for it.

Question 72

The default event-handler method for CheckBox objects is ____________.

Question 73

The ____________ property can be set for RadioButton controls to indicate which button is initially selected.

Question 74

____________ controls can be used to display a list of items from which the user can make single or multiple selections.A scroll bar is automatically added to the control if the total number of items exceeds the number that can be displayed.