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Question 1

What does margin:auto need in order to work?

Answer 1

A width property.

Question 2

What does javascript:void(0) do?

Answer 2

It fires the corresponding event but does not execute the default action (similar to preventDefault());

Question 3

How can we easily toggle a class using jQuery?

Answer 3

toggleClass(altClass);

Question 4

What is a tool to check the integrity of your HTML?

Answer 4

W3 validator.

Question 5

How can we find classes whose name matches a string?

Answer 5

$towers.find(“li[class*=’disk’)”)

Question 6

What is a useful way to see what exactly is going on with your CSS layout?

Answer 6

Use colored backgrounds.

Question 7

What is an XHR?

Answer 7

XMLHttpRequest

Question 8

What are the two ways to call $.ajax()

Answer 8

Pass is a configuration object, or a URL and an optional configuration object.

Question 9

See an example of how to properly create an AJAX object. How is the callback being used? How many are there and why?

Answer 9

The 2 callback functions (one for error and another for success) are defined and then added as values for the success/failure keys in the configuration object.

Question 10

What is a quick way to define the success & error AJAX callbacks?

Answer 10

Make them anonymous functions on the configuration object.

Question 11

In what data format do servers typically respond to an XHR, despite the name?

Answer 11

JSON

Question 12

What are the key methods to utilize JSON objects?

Answer 12

JSON.stringify(), JSON.parse(), jQuery.parseJSON

Question 13

What are convenience methods for AJAX?

Answer 13

Each takes a URL, an optional data object, and an optional callback for a successful request (note there is NO error handling)

$.get( ‘/data/people.html’, function( html ){
$( ‘#target’ ).html( html );
});

$.post( ‘/data/save’, { name: ‘Rebecca’ }, function( resp ) {
console.log( resp );
});

Question 14

How can we pass (form) data t an AJAX request?

Answer 14

By giving it as the ‘data’ key, after serializing it in a query string format:

$( ‘form’ ).submit(function( event ) {
event.preventDefault();

var form = $( this );

  $.ajax({
    type: 'POST',
    url: '/data/save',
    data: form.serialize(),
    dataType: 'json',
    success: function( resp ) {
      console.log( resp );
    }
  });
});

Question 15

When we capture the result of $.ajax() in a variable, what is that called?

Answer 15

It is called a jqXHR