Topic C1

Question 1

How do client side programs avoid overloading of program related requests?

Answer 1

They distribute the load

Question 2

Can client side programs replace server side programming?

Answer 2

No

Question 3

Javascript is a programming language for ______-side programs

Answer 3

client

Question 4

How can javascript code be implemented into an HTML file?

Answer 4

Either directly inserted or linked

Question 5

Where can the script element be placed in an HTML document?

Answer 5

Anywhere

Question 6

When does the browser process the script?

Answer 6

Whenever it reaches it within the HTML file

Question 7

What’s the difference between the async and defer attributes?

Answer 7

async tells a browser to parse the HTML and JS code together, while defer tells the browser to parse the script after the page has been completely loaded

Question 8

Defering a script is equivalent to…

Answer 8

Adding the script in at the end of the HTML file

Question 9

What does a command indicate?

Answer 9

It tells the browser an action to take

Question 10

What is debugging?

Answer 10

The process of locating and fixing a programming error

Question 11

What is an object?

Answer 11

An entity within a browser or web page that has properties and methods

Question 12

A ________ defines an object

Answer 12

property

Question 13

A _______ acts upon a object

Answer 13

method

Question 14

What are the 4 types of javascript objects?

Answer 14

Built-in, browser, document, and customized

Question 15

BOM and DOM stand for what?

Answer 15

Browser object model and document object model

Question 16

Objects within the object hierarchy are referenced by their ______ names

Answer 16

object

Question 17

How can objects be referenced?

Answer 17

object1.object2.object3… where object 1 is at the top of the hierarchy, object2 is the child of object1, and so on

Question 18

What is an object collection and how do you reference a specific member?

Answer 18

Objects organized into groups

collection[idref] or collection.idref

Question 19

What is an efficient approach to reference an element? (Hint: id)

Answer 19

document.getElementbyId(id)

Question 20

How do you access an objects property?

Answer 20

object.property

Question 21

How do you modify an object using a method?

Answer 21

object.method(values)

Question 22

How do you access the HTML code within an element?

Answer 22

element.innerHTML

Question 23

What is the syntax of a javascript function?

Answer 23

function function_name(parameters){
     commands
     return value;
}

Question 24

A javascript command that runs after a specified amount of time has passed is called a ___-_______ command

Answer 24

time-delayed
Time delay is defined using
setTimeout(“command”, delay);
where commandis a JavaScript command and delayis the delay time in milliseconds before a browser runs the command

Question 25

What does a timed-interval command to?

Answer 25

It instructs browsers to run a command repeatedly at a specified interval
setInterval(“command”, interval);

Question 26

What value does javascript return when a mathematical operation is called involving non-numeric values?

Answer 26

NaN. Check is isNaN()

Question 27

How accurate does javascript store numbers?

Answer 27

16 decimal places of accuracy. Can be changed with value.toFixed(n)

Question 28

How could you convert a numeric value into a string?

Answer 28

testString = testNumber + “”;

Question 29

__________ extracts the leading integer value from a text string

Answer 29

parseInt()

Question 30

Are javascript arrays allowed to have multiple data types within them?

Answer 30

Yes

Question 31

How does sort() work on numeric values?

Answer 31

This function sorts numeric values only by their leading digits

Question 32

How do you apply a function to every element in an array?

Answer 32

array.method(callback[, thisArg])
where array is the array, method is the array method, and callback is the name of the function that will be applied to each array item

Question 33

What is an event handler?

Answer 33

A property that controls how an object will respond to an event

Question 34

How does an event handler work?

Answer 34

The event handler waits until the event occurs and then responds by running a function or command block to execute an action

Question 35

How do you add an event handler?

Answer 35

or

object.onEvent = function;

Question 36

What are some examples of events?

Answer 36

oncopy, oncut, onerror, onlaod, onpaste, onresize, etc

Question 37

An _____ ______ is an object that contains properties and methods associated with an event

Answer 37

event object. Ex a mouse click generates info of where, which button. what time it was clicked, etc

Question 38

How would you write an javascript inline style?

Answer 38

object.style.property= “value”;, with property written in camel case

Question 39

______ styles have precedence over ____ ______

Answer 39

inline, style, sheets

Question 40

How would you access the data of an event object in your function?

Answer 40

Pass it as an argument to the function handling the event

ex function myFunc(evt){ code};

Question 41

What are some examples of mouse events that Javascript supports?

Answer 41

click, contextmenu, dblclick, mousedown, etc

Question 42

On the event model, there are four different sections. From least to most specific, what are the sections?

Answer 42

window, document, section, and figure.

Question 43

How is an event processed in the event model?

Answer 43

• First is the capture phase, going from least to most specific.
• Second is the target phase, taking place in the figure.
• Third is the bubbling phase, where it goes to least specific again

Question 44

How is the event listener and event model related?

Answer 44

The event listener listens for events as they propagate through all 3 phases in the event model, and allows a script to respond within any phase.

Question 45

What is a disadvantage of the event handler?

Answer 45

They only respond to events during the target phase of the event model, but not the capture or bubbling phase.

Question 46

What is the difference between and event handler and event listener?

Answer 46

Event handlers can only apply one function to an event, whereas event listeners can apply multiple functions.

Question 47

How do you add an event listener to an object?

Answer 47

object.addEventListener(event, function);

Question 48

What is the difference between the function declaration and the function operator format?

Answer 48

Declaration: Just like another other function definition
Operator: var hello = function() {code}

Question 49

Functions defined with function declarations are created and saved as the browser parses the code prior to the script being run. What does this allow for?

Answer 49

The statements that run the function can be placed prior ti the statement that declares the function.

Question 50

Function operators are evaluated as they appear in the script after the code has been parsed.

Answer 50

They are more flexible than function declarations, allowing them to be placed anywhere a variable can be placed.

Question 51

To create a dialogue box that halts the execution of the program until the user clicks okay, use…

Answer 51

alert(text)

Question 52

How do you add properties to objects?

Answer 52

{ property1 : value 1,
property2 : value2,
…
}

Question 53

How do you add methods to objects?

Answer 53

objectName.methodName = function(args) { commands}

Question 54

How do you store object data into text format?

Answer 54

JSON.stringify()

Question 55

How do you convert a string into a Javascript object?

Answer 55

JSON.parse()