The document provides an introduction to the World Wide Web and basics of PHP programming language. It discusses what the internet and WWW are, how HTTP works, basics of web application development. It then covers installing WAMP or XAMPP on Windows, history and features of PHP versions. Common PHP concepts like variables, data types, operators, control structures like loops and conditional statements are explained.
20240508 QFM014 Elixir Reading List April 2024.pdf
Introduction to web and php mysql
1. Introduction to World Wide Web and basics of PHP
By http://programmerblog.net
By Programmer Blog http://programmerblog.net/
2. What is Internet and World Wide Web?
Internet – Global system of interconnected networks
It is a network of networks that consists of millions of private, public, academic,
business, and government networks of local to global scope.
Use TCP/IP to serve billions of users worldwide.
Voice over Internet Protocol (VoIP) and IPTV. Newspaper publishing, blogging, and
web feeds.
Human interactions through instant messaging, Internet forums, and social
networking sites.
www – Collection of interconnected documents and other resources
System of interlinked hypertext documents contained on the Internet.
http – Hyper Text Transfer Protocol
Hyperlink (or link) is a reference to a document that the reader can directly follow.
Hypertext is text displayed with references (hyperlinks) to other text that the reader
can immediately access
Protocol to transfer hypertext docs from server to client.
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3. Web Application Development
Web application development is the process and practice of
developing web applications.
Request / Response Model
In HTTP, web browsers or spiders typically act as clients, while an
application running on the computer hosting the web site acts as a server
Static vs. Dynamic web pages
Server Side Scripting Languages
J.S.P, ASP. Net Cold Fusion, Python, PHP
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4. W.A.M.P Installation
On windows WAMP or XAMPP can be installed
Web Server – Apache
Server Side Language – PHP
DBMS – MySql
PhpMyAdmin
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5. PHP History
Rasmus Lerdorf - Creator of PHP language
PHP - 1995 Collection of Perl/CGI scripts
PHP/FI was created by Rasmus Lerdorf in 1995, initially as a simple set of Perl
scripts for tracking accesses to his online resume
PHP/FI - 1997 Form Interpreter
Rasmus wrote a much larger C implementation, which was able to
communicate with databases, and enabled users to develop simple
dynamic Web applications .
Personal Home Page / Forms Interpreter
PHP 3.0 June 1998
lots of different databases, protocols and APIs,
Developers joined in and submit new extension modules
PHP: Hypertext Preprocessor.
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6. PHP History
PHP 4
Zend Engine Introduced in 1999
Support for Web servers
Object Oriented Programming
PHP 5
Zend Engine 2.0
XML and Web Services
Object Oriented Support
Exception Handling
A lot of new Features
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7. PHP History
PHP 7 – current version on PHP
is latest version of PHP with lot of improvement. Some of
new features are:
1. Speed
2. Type Declaration
3. Return Type Declarations
4. Error Handling
5. Spaceship Operator
6. Null Coalesce Operator
7. Unicode support for emoji and international characters.
8. Constant arrays using define()
9. Anonymous classes
10.Generator delegation
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8. Why PHP ?
Open Source – Linux – Apache - PHP - MySQL
One of top 5 most popular languages
Small – medium – enterprise level applications
Server Side Scripting
Command Line
Desktop Applications (PHP – GTK)
Available for Windows, Linux, Mac
Many Web Servers – Apache, IIS, nginx, Lighthttpd
Relational / No SQL Databases MySql, Oracle, MSSQL, mongoDB,
PostgreSql
Built in Support – Regex, XML and other functions math etc
Services – LDAP, POP3 and so on
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9. PHP – Online Popular Projects
PHP
Facebook - The world’s biggest social networking platform is written in
PHP.
150 million users and counting, and in my experience, significantly faster
and more stable than competing platforms written in other languages
(e.g. MySpace).
Yahoo! - formerly the world’s largest search engine. Yahoo! makes use
of PHP.
You Tube - the world’s biggest video sharing website uses PHP
technology.
Wikipedia - User contributed web encyclopedia has PHP elements.
Digg.com
Social news network.
Sourceforge.org
The world's largest Open Source software development web site.
Flickr.com
Online photo sharing and storing:
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10. PHP Configuration
PHP.ini
Php configuration file is read when php starts up. Values of different environment
variables can be set in php.ini file. Some of the features are:
Execution time
File upload size and so on
Session paths
Upload file size
Short tags
Error reporting
Safe mode
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11. PHP Basics: Code Blocks
Standard Tags: <?php …… ?>
Short Tags: <?........ ?>
ASP Tags: <%.....%> (Removed from php 7.0)
Script Tags
<script language=“PHP”></script> (Removed from
PHP 7.0)
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12. PHP Basics: Language Constructs
Constructs are elements that are built-into the
language
echo
echo 10;
Every statement ends with semi colon.
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13. PHP Basics: Comments
Single Line Comments -
// this is a single line comment
# this is a single line comment
Multi Line Comments - /* ….. */
/* This is a
Multi line comment
*/
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14. PHP Basics: Data Types
Scalar Data types
Integer (Signed)
String
Floating point
Boolean
Composite
Arrays
Objects
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16. PHP Basics: Data Types
String
echo “ String in double quotes”;
echo ‘ string in single quotes’;
Boolean
True or False;
Composite Data types
Arrays , Objects
Null
Resource
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17. PHP Basics: Variables
PHP is a loosely typed language
Variables are storage container in memory
Variables are identified with $ sign
Valid variables:
[a-zA-Z], numbers, underscores
Variable variable
contents of variable to reference a new variable
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23. PHP Basics: Operator Precedence
$x = 9 + 1 * 10
Expecting result 100 but getting 19 – Multiplication has higher precedence
Highest Precedence * / %
+ - .
< <= > >=
&&
||
And
Xor
Lowest precedence or
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24. PHP Basics: Escape Sequences
" Print the next character as a double quote, not a string closer
' Print the next character as a single quote, not a string closer
n Print a new line character (remember our print statements?)
t Print a tab character
r Print a carriage return (not used very often)
$ Print the next character as a dollar, not as part of a variable
Print the next character as a backslash, not an escape character
$MyString = "This is an "escaped" string";
$MySingleString = 'This 'will' work';
$MyNonVariable = "I have $marks in my pocket";
$MyNewline = "This ends with a line returnn";
$MyFile = "c:windowssystem32myfile.txt";
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25. PHP Basics: Control Structure -1
Control structures allow you to control the flow of
your script
if (expression1) {
…
} elseif (expression2) {
…
} else {
…
}
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27. Control Structures – Switch statement
switch (n)
{
case label1:
//code to be executed if n=label1;
break;
case label2:
//code to be executed if n=label2;
break;
default:
// if n is different from both label1 and label2;
}
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28. PHP Basics: Loops
while - loops through a block of code while a
specified condition is true
do...while - loops through a block of code once,
and then repeats the loop as long as a specified
condition is true
for - loops through a block of code a specified
number of times
foreach - loops through a block of code for each
element in an array
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29. PHP Basics: While Loop
while (condition)
{
code to be executed;
}
$i=1;
while($i<=5)
{
echo "The number is " . $i . "<br />";
$i++;
}
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30. PHP Basics: Do While Loop
do
{
code to be executed;
}
while (condition);
$i=1;
do
{
$i++;
echo "The number is " . $i . "<br />";
}
while ($i<=5);
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31. PHP Basics: For Loop
for (init; condition; increment)
{
code to be executed;
}
for ($i=1; $i<=5; $i++)
{
echo "The number is " . $i . "<br />";
}
Break
Causes the loop to stop and program execution to begin at the
statement immediately following the loop.
Continue
causes the iteration to be skipped
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