CA-404 ADV PHP (BBACA) 2 MARKS || QUESTION WITH ANSWER

CA-404 ADV PHP  (BBACA) 2 MARKS || QUESTION WITH ANSWER

1. What is serialization ?

Ans : Serializing an object means converting it to a bytestream representation that can be stored in a file. This is useful for persistent data; for example, PHP sessions automatically save and restore objects. Serialization in PHP is mostly automatic—it requires little extra work from you, beyond calling the serialize( ) and unserialize( ) functions: $encoded = serialize(something); $something = unserialize(encoded); Serialization is most commonly used with PHP's sessions, which handle the serialization for you. All you need to do is tell PHP which variables to keep track of, and they're automatically preserved between visits to pages on your site. However, sessions are not the only use of serialization—if you want to implement your own form of persistent objects, the serialize( ) and unserialize( ) functions are a natural choice.

2. Enlist the Http Request Methods.

Ans :

1 GET

2 HEAD

3 POST

4 PUT

5 DELETE

6 CONNECT

7 OPTIONS

8 TRACE

3. Name any two variables. of Global Array?

Ans :

$GLOBALS.

$_SERVER.

$_REQUEST.

$_POST.

$_GET.

$_FILES.

$_ENV.

$_COOKIE.

4. Name any two variables of $-SERVER array .

Ans :

$_SERVER['PHP_SELF'] Returns the filename of the currently executing script

$_SERVER['GATEWAY_INTERFACE'] Returns the version of the Common Gateway Interface (CGI) the server is using

$_SERVER['SERVER_ADDR'] Returns the IP address of the host server

5. Explain the purpose of this variable? .

Ans :

$this is a pseudo-variable (also a reserved keyword) which is only available inside methods. And, it refers to the object of the current method.

$this is mostly used in object oriented code.

$this variable is used to call non-static method, if you are trying to call static method then it will throw the error that means $this variable is not available inside the static method

6. How to check whether a Variable is set with the Session?

Ans :

You can check whether a variable has been set in a user's session using the function isset(), as you would a normal variable. Because the $_SESSION superglobal is only initialised once session_start() has been called, you need to call session_start() before using isset() on a session variable.

7. What is introspection  ? 

Ans :

Introspection is the ability of a program to examine an object’s characteristics, such as its name, parent class (if any), properties, and methods. With introspection, you can write code that operates on any class or object. You don’t need to know which methods or properties are defined when you write your code; instead, you can discover that information at runtime, which makes it possible for you to write generic debuggers, serializers, profilers, etc. In this section, we look at the introspective functions provided by PHP.

8. What is $-SERVER ?

Ans :

$_SERVER is a PHP super global variable which holds information about headers, paths, and script locations.

9. Enlist the name of functions to extract basic information about classes in PHP ?.

Ans :

class_exists() – checks whether a class has been defined

get_class() – returns the class name of an object

get_parent_class() – returns the class name of an object’s parent class

is_subclass_of() – checks whether an object has a given parent class

10. methods of PEAR DB ?

Ans : 

The following descriptions discuss each of the PEAR DB module methods. Certain object and parameter names recur throughout the method descriptions in this appendix and have the following conventional meanings:

Connection object methods are called using a $conn object. The object is obtained by calling DB::connect().

Result object methods are called using a $result object. The object is obtained by calling a connection object method such as query() that generates a query result.

The method descriptions indicate data types for return values and parameters. A type of mixed indicates that a value might have different data types depending on how the value is used.

Square brackets ([]) in syntax descriptions indicate optional parameters. When an optional parameter is followed by = value, it indicates that if the parameter is omitted, value is its default value.

The examples print messages and query results as plain text for the most part. This is done to make the code easier to read. However, for scripts intended for execution in a Web environment, you generally should encode output with htmlspecialchars() if it may contain characters that are special in HTML, such as '<', '>', or '&'.

In the descriptions that follow, the term "SELECT statement" should be taken to mean a SELECT statement or any other statement that returns rows, such as DESCRIBE, EXPLAIN, or SHOW.

11. What is XML ?

Ans : 

XML stands for eXtensible Markup Language

XML is a markup language much like HTML

XML was designed to store and transport data

XML was designed to be self-descriptive

XML is a W3C Recommendation

12. What is WSDL ?

Ans : 

WSDL stands for Web Services Description Language

WSDL is used to describe web services

WSDL is written in XML

13. Name any two parameters of mysql_connect().

Ans :

server

The MySQL server. It can also include a port number. e.g. "hostname:port" or a path to a local socket e.g. ":/path/to/socket" for the localhost.

If the PHP directive mysql.default_host is undefined (default), then the default value is 'localhost:3306'. In SQL safe mode, this parameter is ignored and value 'localhost:3306' is always used.

username

The username. Default value is defined by mysql.default_user. In SQL safe mode, this parameter is ignored and the name of the user that owns the server process is used.

password

The password. Default value is defined by mysql.default_password. In SQL safe mode, this parameter is ignored and empty password is used.

new_link

If a second call is made to mysql_connect() with the same arguments, no new link will be established, but instead, the link identifier of the already opened link will be returned. The new_link parameter modifies this behavior and makes mysql_connect() always open a new link, even if mysql_connect() was called before with the same parameters. In SQL safe mode, this parameter is ignored.

14. Name any two elements of xml document structure ?

Ans :

An element can contain:

text

attributes

other elements

or a mix of the above

<title>, <author>, <year>, and <price> have text content because they contain text (like 29.99).

<bookstore> and <book> have element contents, because they contain elements.

<book> has an attribute (category="children").

15. Enlist PHP Dom's functions?

Ans : 

DOMAttr 

PHP DOMAttr __construct() Function

PHP DOMAttr isId() Function

DOMCdataSection

PHP DOMCdataSection __construct() Function

DOMCharacterData

PHP DOMCharacterData appendData() Function

PHP DOMCharacterData deleteData() Function

PHP DOMCharacterData insertData() Function

PHP DOMCharacterData replaceData() Function

PHP DOMCharacterData substringData() Function

DOMComment

PHP DOMComment __construct() Function

16. Give any two applications of AJAX

ANS :

Ajax is used in any web application in which a small amount of data needs to be saved without posting back to an entire page.

One major application of AJAX is in login forms where users can enter their login details directly on the original page.

Another major application can be for voting on social bookmarking sites so that they can vote for something easily and quickly.

17. Enlist the methods of XML HTTPREQUEST object?

Ans :

abort() Cancels the current request

getAllResponseHeaders() Returns header information

getResponseHeader() Returns specific header information

open(method,url,async,uname,pswd) Specifies the type of request, the URL, if the request should be handled asynchronously or not, and other optional attributes of a request

method: the type of request: GET or POST

url: the location of the file on the server

async: true (asynchronous) or false (synchronous)

send(string) send(string) Sends the request off to the server.

string: Only used for POST requests

18. Types of parser in XML &

Ans :

To read and update, create and manipulate an XML document, you will need an XML parser.

In PHP there are two major types of XML parsers:

Tree-Based Parsers

Event-Based Parsers

Tree-Based Parsers

Tree-based parsers holds the entire document in Memory and transforms the XML document into a Tree structure. It analyzes the whole document, and provides access to the Tree elements (DOM).

This type of parser is a better option for smaller XML documents, but not for large XML document as it causes major performance issues.

Example of tree-based parsers:

SimpleXML

DOM

Event-Based Parsers

Event-based parsers do not hold the entire document in Memory, instead, they read in one node at a time and allow you to interact with in real time. Once you move onto the next node, the old one is thrown away.

This type of parser is well suited for large XML documents. It parses faster and consumes less memory.

Example of event-based parsers:

XMLReader

XML Expat Parser

19. What is SOAP ?

Ans :

SOAP is an acronym for Simple Object Access Protocol. It is an XML-based messaging protocol for exchanging information among computers. SOAP is an application of the XML specification.

Points to Note

SOAP is a communication protocol designed to communicate via Internet.

SOAP can extend HTTP for XML messaging.

SOAP provides data transport for Web services.

SOAP can exchange complete documents or call a remote procedure.

SOAP can be used for broadcasting a message.

SOAP is platform- and language-independent.

SOAP is the XML way of defining what information is sent and how.

SOAP enables client applications to easily connect to remote services and invoke remote methods.

20. What is Web serives ?

Ans :

A Web Service is can be defined by following ways:

It is a client-server application or application component for communication.

The method of communication between two devices over the network.

It is a software system for the interoperable machine to machine communication.

21. What is setcookie () function?

Ans :

The setcookie() function defines a cookie to be sent along with the rest of the HTTP headers.

A cookie is often used to identify a user. A cookie is a small file that the server embeds on the user's computer. Each time the same computer requests a page with a browser, it will send the cookie too.

22. What is UDDI ?.

Ans :

UDDI is an XML-based standard for describing, publishing, and finding web services.

UDDI stands for Universal Description, Discovery, and Integration.

UDDI is a specification for a distributed registry of web services.

UDDI is a platform-independent, open framework.

UDDI can communicate via SOAP, CORBA, Java RMI Protocol.

23. Enlist functions in php to connect to the mysql.

Ans :

Connect using mysqli extension (Recommended)

Connect using PDO (Recommended)

Connect using traditional legacy mysql_ functions (Deprecated)

mysqli_connect function

mysqli_select_db function

mysqli_query function

mysqli_num_rows function

mysqli_fetch_array function

mysqli_close function