Deck 9: Additional Javascript Basics: Window Object, If Statement, Strings, Numbers, and Input Validation

Question 1

When should you use dialog boxes (alert, confirm, and prompt) for input and output?

A) Dialog boxes are new with HTML5 and, as such, they are gaining traction as the preferred technique for all input and output.
B) Use dialog boxes only when you want to draw sharp attention to something and you want to force the user to deal with the issue immediately.
C) Use dialog boxes for all text input, but not for numerical input.

Answer 1

B

Question 2

Consider the following three strings:
"to be or not to be", "to", "tooth"
Which of the following shows the strings sorted into ascending lexicographical order (words that are considered less than other words should be at the left).

A) "to be or not to be", "to", "tooth"
B) "to", "tooth", "to be or not to be"
C) "to", "to be or not to be", "tooth"

Answer 2

C

Question 3

To embed a backslash character (\) within a JavaScript string, you need to use the ______ escape sequence.

Answer 3

\\

Question 4

Provide a functionally equivalent, shorter version of the following code:
window.document.getElementById["name"]

Question 5

The following code generates a dialog box that contains a question and an input box:
prompt("What's your favorite color?", "");
Initially, what displays inside the input box?

Question 6

Suppose a variable x holds "dog". After the following code gets executed, what does x hold?
x += "fish";

Question 7

When the following code executes, what message does the dialog box display?
var month = "January";
if (month.toLowerCase() == "january") {
alert("It is " + month + "!");
}

Question 8

After the following code executes, what does x hold?
var location = "Taos, NM";
var x = location.charAt(location.length - 1);

Question 9

After the following code executes, what does x hold?
var animal = "porcupine";
var x = animal.lastIndexOf("p", 3);

Question 10

What does the following expression evaluate to?
39 % 10 / 4

Question 11

Which of the following is a function of the <code>window</code> object's <code>location</code> property?

A) Holds the URL of the current web page
B) Displays the title of the current web page
C) Displays the geographical position of the user's computer

Question 12

What is the syntax for generating a dialog that displays a message and does not receive input?

A) <code><msg>message</msg></code>
B) <code><quote>message</quote></code>
C) <code>alert(message);</code>
D) <code>prompt(message);</code>

Question 13

What is the syntax for generating a dialog that prompts the user to answer yes or no to a question?

A) <code><prompt>message</prompt></code>
B) <code><ask>message</ask></code>
C) <code>alert(message);</code>
D) <code>confirm(message);</code>

Question 14

What is an <code>if</code> statement's condition?

A) A condition is a break in a web page that displays as a blank line.
B) A condition is a pause generated by a screen reader.
C) A condition is a question, surrounded by parentheses, that evaluates to true or false.

Question 15

An <code>if</code> statement is an example of a:

A) declaration statement.
B) branching statement.
C) looping statement.

Question 16

Which of the following statements is correct regarding an initialization statement?

A) It tells the browser engine that the program uses JavaScript for its language.
B) It links the web page's HTML code to its JavaScript code.
C) It is a combination of a variable declaration and an assignment.

Question 17

The <code>window</code> object's <code>screen</code> property holds information about the monitor that is being used.

Question 18

A named constant is a special variable whose value is fixed.

Question 19

To break/split a string in JavaScript, you should terminate the first part of the string with a closing quote, insert a(n) ______, and start the next line's continuation string with an opening quote.

Question 20

A(n) __________ is a pictorial representation of the logic flow of a computer program.

Question 21

Proper coding conventions suggest that when there are JavaScript statements inside of braces ({}), you should do which of the following?

A) Indent the statements inside the braces.
B) Position each statement's first character in the same column as the braces.
C) Separate the statements with commas, not semicolons.

Question 22

How can you test two strings to see if they are equal?

A) Call the equal method.
B) Call the equals method.
C) Use the = operator.
D) Use the == operator.

Question 23

Suppose you have a variable named character. What is the best way to assign a double quote (") to character?

A) character = "
B) character = '"';
C) character = "'";
D) character = "\'";

Question 24

The *:not(a) pseudo-class selector selects which of the following?

A) All noteworthy elements
B) All elements except for a elements (links)
C) Elements that are siblings of the current element

Question 25

How can you round a price variable's value to the hundredths place (e.g., 204.89)?

A) Use the remainder operator, price % 2.
B) Use the division operator, price / 2.
C) Call the round method, price.round(2).
D) Call the toFixed method, price.toFixed(2).

Question 26

The window object is known as the global object because all of its members are global.

Question 27

A dialog box is a control that supports verbal two-way communication between the user and the computer.

Question 28

A block statement (zero or more statements surrounded by braces) can be used anywhere a standard statement can be used.

Question 29

For the "if, else if, else" form of the if statement, if a condition is found to be true, that condition's block statement is executed. Then, all the other conditions are skipped, and control flows down to the statement below the entire if statement.

Question 30

The output element is for holding the result of a user's action.