jQuery Quiz Questions 11-20

March 31, 2014

Following on from jQuery Quiz Questions 1-10 here are questions 11-20. Hopefully you might learn something new about jQuery you didn’t know before. Once more if you find any mistakes please feel free to leave a comment with corrections. Enjoy!

Question 11

Which of the following is the correct way to check which key was pressed using jQuery?

Answers

$('#txtValue').keypress(function (event) {
    $('#txtvalue').alert((event.keyCode));
});

$(‘#txtValue’).keypress(function (event) {
    alert(String.fromCharCode((event.keyCode)));
});

$(‘#txtValue’).keypress(function (event) {
    alert(fromCharCode((event.keyCode)));
});

$(‘#txtValue’).keypress(function (event) {
    $(‘#txtvalue’).alert((event.which));
});

Correct Answer

$(‘#txtValue’).keypress(function (event) {
    $(‘#txtvalue’).alert((event.which));
});

API: http://api.jquery.com/keypress/

Question 12

Consider the following code snippet:

$('#ul1 li').on('click', function1);
$('#ul1').after('

Last item

');

Is function1 executed if “lastLi” is clicked?

Answers

Correct Answer
no. The .after() function adds the list item outside the UL tag.

Question 13

$("ul#myId > li");

What does the above statement return?

Answers

A set of tags whose id is “li”.
A set of tags which contains class “li”.
A set of li tags which are children of ul tags that have “myId” class.
A set of li tags which are children of ul tags that have “myId” id.

Correct Answer
A set of li tags which are children of ul tags that have “myId” id.

Question 14

Consider the following code snippet:

$('#table1').find('tr').filter(function (index) {
    return index % 3 == 0
}).addClass('firstRowClass');

The result of the above code snippet is ___.

Answers

the rows of table1 at order 3n + 1 (n = 0, 1, 2, …) have class firstRowClass
the rows of table1 at order 3n (n = 1, 2, …) have class firstRowClass
all rows of table1 have class firstRowClass
no rows of table1 have class firstRowClass

Correct Answer
the rows of table1 at order 3n + 1 (n = 0, 1, 2, …) have class firstRowClass
see answer in action: https://jsfiddle.net/jquery4u/zJW3B/

Question 15

Which of the following is the correct way to move an element into another element?

Answers

```
$('#source').prependTo('#destination');
```
```
$("#source").add("#destination");
```
```
$("#source").html("#destination");
```

$("#source").add().html().("#destination");

Correct Answer

$("#source").add("#destination");

Question 16

Consider the following code snippet:

$('span.item').each(function (index) {
    $(this).wrap('Item');
});

Essentially, what does this code snippet do?

Answers

Wraps each span tag that has class item within a li tag.
Inserts each span tag that has class item into a li tag.
Inserts Item into each span that has item class.
Replaces each span tag that has class item with a
Item

Correct Answer
Wraps each span tag that has class item within a li tag.
see answer in action: https://jsfiddle.net/jquery4u/gv2vq/

Question 17

What is the result of the following code snippet?

jQuery.unique([1, 2, 2, 3, 3, 1]);

Answers

[1, 2, 3].
[3, 2, 1].
[1, 1, 2, 2, 3, 3].
None of the above.

Correct Answer
[1, 2, 3].
see answer in action: https://jsfiddle.net/jquery4u/gkJsP/

Question 18

Consider the following code snippet:

$('#table1').find('tr').hide().slice(10, 20).show();

What is the result of this code snippet?

Answers

Showing table1’s rows from 11th to 20th.
Showing table1’s 20 rows from 10th.
Deleting rows of table1 from 10th to 20th.
Deleting 20 rows of table1 from 10th onward.

Correct Answer
Showing table1’s rows from 11th to 20th.
see answer in action: https://jsfiddle.net/jquery4u/MQjer/

Question 19

$("div").find("p").andSelf().addClass("border");

The statement adds class border to ___.

Answers

all p tags enclosed in div tag
all div tags and p tags in div tags
all div tags
all p tags

Correct Answer
all div tags and p tags in div tags
see answer in action: https://jsfiddle.net/jquery4u/eUBup/

Question 20

Which of the following statements return(s) a set of p tags that contain “jQuery”?

Answers

```
$('p:contains(jQuery)');
```
```
$('p:contains("jQuery")');
```
```
$('p:has("jQuery")');
```
1 and 2
1 and 3

Correct Answer
1 and 2
see answer in action: https://jsfiddle.net/jquery4u/cAnHC/