Javascript, DOM and AJAX

Question 1

What is the format of the HTML script tag?

Answer 1

< script type=”text/javascript” >
// Code here
< /script >
Technically, type attribute is optional in HTML5.
Very old browsers might need the code inside the script tag commented out with < !– and – >

Question 2

What is the noscript tag?

Answer 2

Inverse of the script tag. Content shows when JS is not available. It is deprecated and not necessary if you create JS that is unobtrusive.

Question 3

Easiest way to prompt and alert user.

Answer 3

With
var name = prompt(“Enter your name”, “”);
and
alert(“Hello, “ + name);

Question 4

How to return the type of a variable?

Answer 4

typeof() returns type of data passed to it.

Question 5

How to convert a float to an integer?

Answer 5

parseInt()

Question 6

How to explicitly convert string to a number?

Answer 6

Number() or parseFloat() or parseInt()

Question 7

How to explicitly create a string object?

Answer 7

var myStr = new String(“abc”);