Web Technologies II - Questions by

JS-Constructor Overloading

vidhurojit — 2017-01-02 16:27:32 UTC

Can JS constructors be overloaded?
No.They cannot be overloaded as JavaScript is a dynamically typed language

JS: Editing Constructors

vidhurojit — 2017-01-03 09:23:03 UTC

function Foo() {
}
Foo.prototype.bar = "I'm bar on Foo.prototype";
Foo.bar = "I'm bar on Foo";
var f = new Foo();
console.log(f.bar)//gives undefined. why does is not print "I am foo on bar"

Explanation at http://stackoverflow.com/questions/9582341/adding-new-properties-to-constructor-function-without-prototype

JS Inheritance

vidhurojit — 2017-01-05 00:06:20 UTC

TO designate Rectangle as the parent of square why cant we say
Square.prototype=Rectangle.prototype?

ANS In this case any methods added to Square.prototype will be accessible to rectangle objects as well . These are object references

JS Prototypal Inheritance

vidhurojit — 2017-01-05 00:08:00 UTC

What happens behind the scenes when you say
Square.prototype=new Rectangle()

AJAX: When you make repeated calls to the same server resource wont the resource be cached?

vidhurojit — 2017-01-05 16:22:08 UTC

Ans Including teh following code in the page prevents it from being cached

JS Inheritance

vidhurojit — 2017-01-06 05:24:13 UTC

Is multiple inheritance possible in JavaScript?
ANS

Some object-oriented languages allow multiple inheritance. That is, an object can inherit the properties and values from unrelated parent objects. JavaScript does not support multiple inheritance.

Inheritance of property values occurs at run time by JavaScript searching the prototype chain of an object to find a value. Because an object has a single associated prototype, JavaScript cannot dynamically inherit from more than one prototype chain.

AJAX Techniques

vidhurojit — 2017-01-09 09:20:53 UTC

WHat happens if we put target of a form as div in the page

AJAX

vidhurojit — 2017-01-09 09:21:26 UTC

Does clicking form.submit() work same as clicking the submit button. Especially in terms of "required" attribute

AJAX IMAGES

vidhurojit — 2017-01-09 09:22:24 UTC

Is Content -type header always requred?

CROSS DOMAIN ACCESS IN IFRAMES

vidhurojit — 2017-01-10 04:14:04 UTC

http://softwareas.com/cross-domain-communication-with-iframes/

TARGET ATTRIBUTE OF A FRAME

vidhurojit — 2017-01-10 05:34:10 UTC

The acceptable values for the target attribute of a frame are

READY STATE

vidhurojit — 2017-01-15 09:17:56 UTC

Q:What do the different readyState values(0 through 4) mean?

XHR BINARY FETCH

vidhurojit — 2017-01-20 03:17:08 UTC

Why are large size blobs not downloading?

HOW CAN YOU SET UP MULTIPLE HOSTS ON XAMPP

vidhurojit — 2017-01-24 23:20:13 UTC

https://delanomaloney.com/2013/07/10/how-to-set-up-virtual-hosts-using-xampp/

Multistage download versus Streaming

2017-03-29 11:37:30 UTC

How is Streaming different from multistage download? Both are used to display data part by part on the web page to give the user a faster service.

In multistage download the client issues a request and the a response is sent with respect to it. In streaming a persisitent connection is kept open and multiple responses are sent by checking readystate 3

Madam, Please send the Makeup Scheme and Solutions for both PESIT and PESU.

2017-05-05 14:18:18 UTC

done

WebSockets

2018-04-15 16:04:27 UTC

How to implement websockets using just javascript ( not even jquery ) and php?

Why is ob_start used ?What is the difference between ob_flush and flush ?

2020-05-25 12:12:35 UTC