Web Technology Experts Notes

Wednesday, 10 August 2016

Twitter Bootstrap Interview Questions and Answers

Question: How to make twitter bootstrap menu dropdown on hover rather than click?

ul.nav li.dropdown:hover > ul.dropdown-menu {
    display: block;    
}

Question: How can I make Bootstrap columns all the same height??

.row {
  display: -webkit-box;
  display: -webkit-flex;
  display: -ms-flexbox;
  display: flex;
  flex-wrap: wrap;
}
.row > [class*='col-'] {
  display: flex;
  flex-direction: column;
}

Question: What is sr-only in Bootstrap 3??
It is class used to hide information intended only for screen readers from the layout of the rendered page.

Question: How to disallow twitter bootstrap modal window from closing?

<a data-backdrop="static" data-controls-modal="my_div_id" data-keyboard="false" href="https://www.blogger.com/blogger.g?blogID=5911253879674558037#"></a>

Question: What are different 4 tiers in twitter bootstrap?

Extra small devices like smartphones (.col-xs-*)
Small devices like tablets(.col-sm-*)
Medium devices like laptops (.col-md-*)
large devices like laptops/desktops(.col-lg-*)

Question: How to use media queries in twitter bootstrap 3?

@media(max-width:767px){}
@media(min-width:768px){}
@media(min-width:992px){}
@media(min-width:1200px){}

Question: How to use media queries in twitter bootstrap 4?

@media(min-width:34em){}
@media(min-width:48em){}
@media(min-width:62em){}
@media(min-width:75em){}

Question: What is an em?
An em is a unit in the field of typography, One em is equal to the 16 point size.

Question: How to open a Bootstrap modal?

$('#myModalId').modal('toggle');
$('#myModalId').modal('show');
$('#myModalId').modal('hide');

Question: How to make responsive image with align center?

.img-responsive {
    margin: 0 auto;
}

Question: How to create Confirm box before deleting modal/dialog?
Add data-target="#confirm-delete-id" in A tag


<a data-href="/delete-rec?id=203" data-target="#confirm-delete-id" data-toggle="modal" href="https://www.blogger.com/blogger.g?blogID=5911253879674558037#">Delete record #203</a>

Add HTML for confirmation box

<div aria-hidden="true" aria-labelledby="myModalLabel" class="modal fade" id="confirm-delete-id" role="dialog" tabindex="-1">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-header">
</div>
<div class="modal-body">
</div>
<div class="modal-footer">
<button class="btn btn-default" data-dismiss="modal" type="button">Cancel</button>
                <a class="btn btn-danger btn-ok" href="https://www.blogger.com/null">Delete</a>
            </div>
</div>
</div>
</div>

Question: How to disabled the button?

$('#buttonId').prop('disabled', true);

Tuesday, 9 August 2016

What is RTMP, RTMPT, RTMPE, RTMPTE and RTMPS protocol?

Question: What is RTMP?
The Real-Time Messaging Protocol (RTMP) is a streaming protocol designed by Adobe for transmission of audio, video between the flash player and server.

Question: What is RTMPT?
RTMPT is tunneled Version of RTMP.
RTMPT is designed to get rid of firewalls by sending stream packets through the standard web port.

Question: Which is better RTMP OR RTMPT?
RTMP performance is better that RTMPT.
We should use RTMPT only when RTMP is not possible due to firewalls.

Question: What is RTMPE?
RTMPE is encrypted version of RTMP.
Basically In RTMPE there is an additional security level as compare to RTMP.

Question: What is RTMPTE?
RTMPTE is encrypted version of RTMPT.
Basically In RTMPTE there is an additional security level as compare to RTMPT.

Question: What is RTMPS?
RTMPS is RTMP over a TLS/SSL connection.

Question: What is RTMFP?
Full form of RTMFP is Secure Real-Time Media Flow Protocol. This protocol is developed by Adobe Systems for encrypted. It is efficient multimedia delivery through both client-server and peer-to-peer models over the Internet.

Question: Who uses the 1935 port by default?
RTMP and RTMPE with TCP Transport.
RTMFP with with UDP Transport.

Question: What are different ports used by Media Servers?
Following are different default ports used by Media Server.

Port	Protocol	Transport
1935	RTMP/E	TCP
1935	RTMFP	UDP
80	RTMP, RTMPT, HTTP	TCP
8134	HTTP	TCP
1111	HTTP, RTMP	TCP

Question: What is TCP?
Full form of TCP is Transmission Control Protocol.
It is standard that defines how to establish and maintain a network conversation.
It can also work with IP (internet protocol), which define how to exchange packet of data with each other.
TCP keep maintained the connection til the programs finished their exchanging messages.

Question: What is UCP?
Full form of UDP is User Datagram Protocol.
UDP is communications protocol to TCP used primarily for establishing low-latency and loss tolerating connections between applications on the Internet.