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PHP Section One - An Introduction to PHP
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> PHP Thirteen - Manipulate a MySQL
Database
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> Walkthrough Four - The Code for the Forum
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50 ESSENTIAL PHP TUTORIAL AND
EXAMPLES FOR BEGINNERS
25+ PHP Tutorials &
Techniques
PHP is
no doubt very useful programing language now a days. It is basically made for
creating dynamic web pages. It’s importance increases day by day because it is
now using in content management systems like wordpress, Joomla, etc. Today i
have collected 25+ php tutorials. In this list i includes tutorials from
beginner to advanced level.
1-
Image Resizing Made Easy with PHP
2-
Retrieve Google Analytics Visits and PageViews with PHP
3- 9
Useful PHP Functions and Features You Need to Know
4- How
to Create a PHP/MySQL Powered Forum from Scratch
5- How
to Properly Create a Website Index Page Using PHP
6-
Creating a Bar Graph using CSS and PHP
7- How
to Validate Forms in both sides using PHP and jQuery
8- How
to Send Text Messages with PHP
9-
Rabid Ratings
10-
Caching Dynamic PHP pages easily
11-
Libchart
12-
Reading Excel Documents from PHP applications
13-
Retrieve Your Gmail Emails Using PHP and IMAP
14-
Using PHP Sessions
15-
Create a Photo Admin Site Using PHP and jQuery
16-
Vertical Bar Graphs with CSS and PHP
17-
Email Error Logs with PHP
18-
Retrieve Google Analytics Visits and PageViews with PHP
19-
Sanitize and Validate Data with PHP Filters
20-
File upload in PHP, Securing the things
21-
Build a JSON and PHP product gallery
22-
Easy PHP Pagination
23-
Logging processes with PHP
24- PHP
ajax login form using Jquery
25-
jQuery and PHP inline editing
26- How
to Code a Signup Form with Email Confirmation
27-
Create a shoutbox using PHP and AJAX (with jQuery)
How To Upload Images And Files Php Upload Images to Webserver HTML Form PHP
Function # UPLOAD FILE function upload_file(){ echo '
Using Php Cookies Variables Using Cookie Variables in PHP Setting cookies
in php is pretty straight forward. There is a php function: setcookie(); This
function mu
How To Unzip Files On Your Free Hosting Account Uzipping Files on Your Web Server If you are
using a free hosting account with godaddy.com and many of the other Free hosts
out there, you may have found that they don't offer you a lot o
Passing Data From One Form To Another Form Php Passing data from one form to another form To
pass php data from a form and then catch that data into another form one way to
accomplish this task is to intermi
Storing Image Locations Mysql Storing Image Url Location in Mysql Database
Storing images in the Mysql Database using php can be done by encoding the
whole image with a function called base64enco
What Is Php Explanation
of PHP Basic Syntax --New to PHP Php is a language that is very much like
writing c. The best feature of PHP versus c is that it is designed pri
How To Use Dreamweaver Dreamweaver - WISIWIG Dreamweaver is a tool
that arguably could be called the industry standard for web design .
Dreamweaver, is an Adobe product that originally b
Notepad Plus Notepad++
Download Notepad Plus Plus Notepad plus plus is an open source, free text
editor. It is
How To Open Create Write Files Php Php file functions, Opening a file in php,
reading a file in php, writing a file in php In this tutorial we will look at
the most commonly used file functions used in php. The
Stop Form Spam Captcha Php PHP -- How to Protect My Email Form / Contact
Form Against Spam Bots Author: D.Shaun Morgan Versions and Skill Level PHP 5
Retreive Images Mysql Php Php How to get images out of mysql database with
php and use them on my webpages Author: D.Shaun Morgan PHP Version - PHP
5x
How To Make Money Online Php Making Money on the Internet Sign up for this
series of free money making articles Name:
Store Images Mysql Php Php Storing Images in Mysql Database Tutorial
Outline: Creating a Test Mysql Database Example php Database Functio
Php Example Post Array Php Visual example of how PHP handles the
super-global array variable "$_POST" Author: D.Shaun Morgan Versions
and Skill Level
Php Arrays Php Passing arrays to another page Author:
D.Shaun Morgan Versions and Skill Level PHP Version - PHP 5x Reader skill
level
How To Write Php Functions Php How to Write PHP functions Part 1 Author:
D.Shaun MorganVersions and Skill Level PHP 5 Reader skill level - Begin
How To Write Html Form PHP Php When learning PHP to build a website, one of
the very first things that any newcomer, or beginner needs to learn is how to
use HTML or XHTML (both will mean the same for this tutorial.) fo
Register Globals Long Arrays Php Security, php.ini, register_globals and
register_long_arrays Author: D.Shaun Morgan Versions and Skill Level PHP
Version - PHP 5x
How To Install Php 5 Php This is a quick start beginner's how-to
manual explaining how to quickly setup a PHP 5 installation on a Windows XP PC.
You must have an Apache webserver installed and working on your personal comp
Php Passing Variables Php Pass Variables from One Page to Another --
PHP Author: D.Shaun Morgan Tutorial Outline : Passing PHP variables with $_
PHP Basics
Lesson Goals
·
What is PHP
·
How PHP works.
·
To write a simple PHP page.
·
To understand and work with
simple PHP variables.
·
To use PHP operators.
·
To pass values from one page to
another via the URL.
Lesson Activities
How
PHP Works
When a user navigates in her
browser to a page that ends with a 
.php extension, the request is sent to a web server, which
directs the request to the PHP interpreter.
As
shown in the diagram above, the PHP interpreter processes the page,
communicating with file systems, databases, and email servers as necessary, and
then delivers a web page to the web server to return to the browser.
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online PHP courses, which
includes videos and exercises in addition to the content in this PHP tutorial.
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The
php.ini File
Before we look at PHP syntax, we
should briefly mention the php.ini file.
This is a plain text file that is used to configure PHP. When the PHP
interpreter is started, it reads the php.ini file
to determine what settings to use. We will mention this file from time to time
throughout the course, but for now, it is enough that you are aware of its
existence.
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PHP course, which includes videos and
exercises in addition to the content in this PHP tutorial. Not sure if you want
to pay for that? Register for a free demo of the course.
Basic
PHP Syntax
PHP Tags
PHP
code must be contained in special tags so that the PHP interpreter can identify
it. Depending on the PHP configuration, these tags can take several forms:
|
This is the most commonly used
(and recommended) form. It is known as the XML style, because it can be used
inside of an XML document without causing the document to become poorly
formed.
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HTML or Script style tags.
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"Short" tags. Must be
enabled via the short_open_tag php.ini configuration file directive.
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ASP-style tags. Must be enabled
via the asp_tags php.ini configuration file directive.
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In
this manual, we will use the first form shown as it is the most common and the
most portable.
PHP Statements and Whitespace
PHP
statements must be inside of PHP tags to be processed by the PHP interpreter.
Each PHP statement must end with a semi-colon, which tells the PHP interpreter
that the statement is complete. If a semi-colon does not appear at the end of a
line, the interpreter will assume that the statement continues onto the next
line.
The
PHP interpreter condenses all sequential whitespace in PHP scripts to a single
whitespace. This convenient feature allows PHP developers to structure their
code in a readable format without being concerned about the effects of line
breaks and tabs.
Comments
PHP
has two forms of comments:
·
Single-line comments begin with a
double slash (//).
·
Multi-line comments begin with
"/*" and end with "*/".
Syntax
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// This is a single-line comment/* This is a multi-line comment.*/ |
PHP Functions
There are literally hundreds of
built-in PHP functions that do everything from returning the current date and
time on the server to pulling data out of a database. A function might take
zero arguments (e.g,
phpinfo(), which returns information on the PHP environment) or
it might take several arguments (e.g, mail(), which takes three required and two optional
arguments). The syntax for calling a function is straightforward:
Syntax
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1
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function_name(arguments); |
The example below shows how the
phpinfo() function works.
Code Sample:
PhpBasics/Demos/PhpInfo.php
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<!DOCTYPE HTML><html><head><meta charset="UTF-8"><title>PHPINFO</title></head><body><?php //Output information on the PHP environment phpinfo();?></body></html> |
Introduction to php.net
PHP functions are well documented
at http://www.php.net. You can quickly look up documentation on a function
by going to http://www.php.net/function_name. For example, to see documentation on
phpinfo(), go to http://www.php.net/phpinfo.
Hello World!
It
is an unwritten rule that every programming course must contain a "Hello
World!" script. Here it is:
Code Sample:
PhpBasics/Demos/HelloWorld.php
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<!DOCTYPE HTML><html><head><meta charset="UTF-8"><title>Hello World!</title></head><body><?php //Write out Hello World! echo 'Hello World!';?></body></html> |
Notice
the following about the above code:
·
Code between
<?php and ?> is processed by the PHP interpreter.
·
The
echo command is used to print text back to the browser.
This
code isn't very exciting. In fact, PHP doesn't buy us anything here as we could
have just as easily output the result using straight HTML. There is nothing dynamic
about this script. After learning about variables, we'll take a look at some
more interesting examples.
Like this PHP tutorial? Try our self-paced
online PHP course, which
includes videos and exercises in addition to the content in this PHP tutorial.
Not sure if you want to pay for that? Register for a free demo of the course.
Variables
PHP variables begin with a dollar
sign (
$) as shown below.
Syntax
$varName = "Value"; |
Variable Types
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Variable Type
|
Explanation
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Integer
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whole number
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Double
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real number
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String
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string of characters
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Boolean
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true or false
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Array
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list of items
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Object
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instance of a class
|
Variable Names (Identifiers)
Variable,
function and class names are all identifiers and all follow the rules above,
with the exception that function names are not case sensitive.
·
consist of letters, digits,
underscores and dollar signs
·
cannot begin with a digit
·
are case sensitive
Type Strength
PHP
is weakly typed, meaning that variables do not need to be assigned a type (e.g,
Integer) at the time they are declared. Rather, the type of a PHP variable is
determined by the value the variable holds and the way in which it is used.
Hello Variables!
Here
is the "Hello World!" script again, but this time we use a variable.
Code Sample:
PhpBasics/Demos/HelloVariables.php
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<?php $greeting = 'Hello World!';?><!DOCTYPE HTML><html><head><meta charset="UTF-8"><title><?php echo $greeting; ?></title></head><body><?php echo $greeting;?></body></html> |
This time the string "Hello
World!" is stored in the
$greeting variable, which is output in the title and body of the
page with an echo command.
Variable Scope
A
variable's scope determines the locations from which the variable can be
accessed. PHP variables are either superglobal, global, or local.
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Variable Scope
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Explanation
|
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superglobal
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Superglobal variables are
predefined arrays, including
$_POST and$_GET. They are accessible from anywhere on the
page. |
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global
|
Global variables are visible
throughout the script in which they are declared. However, they are not
visible within functions in the script unless they are re-declared within the
function as global variables.
|
|
function
|
Variables in the function scope
are called local variables. Local variables are local to the function in
which they are declared.
|
Superglobals
Again, superglobal variables are
predefined arrays, including
$_POST and $_GETand are accessible from anywhere on the page. The
complete list of superglobals is shown below.
·
$_GET -
variables passed into a page on the query string.
·
$_POST -
variables passed into a page through a form using the post method.
·
$_SERVER -
server environment variables (e.g, $_SERVER['HTTP_REFERER']returns the URL of the referring page).
·
$_COOKIE -
cookie variables.
·
$_FILES -
variables containing information about uploaded files.
·
$_ENV -
PHP environment variables (e.g, $_ENV['HTTP_HOST'] returns the name of the host server.
Which environment variables are
available depends on the specific server setup and configuration.
·
$_REQUEST -
variables passed into a page through forms, the query string and cookies.
·
$_SESSION -
session variables.
The elements within superglobal
variables can be accessed in three different ways, which the authors of PHP and MySQL Web Development refer to as short
style,medium style, and long style.
PHP
& MySQL Web Develpoment, Third Edition.
|
Style
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Syntax (using
$_GET) |
Notes
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|
Short
|
$varname |
·
Convenient, but it makes it difficult to distinguish
superglobal variables from other variables in the code.
·
Requires
register_globals config setting to be on. |
|
Medium
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$_GET['varname'] |
·
Recommended approach.
·
Happy medium between convenience and clarity.
·
Not available before v. 4.1.
|
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Long
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$HTTP_GET_VARS['varname'] |
·
Inconvenient to type.
·
Deprecated, but still supported in current versions.
·
Can be disabled via theregister_long_arrays directive in thephp.ini file.
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Many
of these superglobals will be covered later in the course.
Constants
Constants are like variables
except that, once assigned a value, they cannot be changed. Constants are
created using the
define() function and by convention (but not by rule) are in
all uppercase letters. Constants can be accessed from anywhere on the page.
Syntax
define('CONST_NAME',VALUE); |
Variable-Testing and Manipulation
Functions
PHP
provides built-in functions for checking if a variable exists, checking if a
variable holds a value, and removing a variable.
To output the results of these
functions to a browser, use the var_dump() function (e.g.
var_dump(isset($a));).
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Function
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Explanation
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Example
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isset() |
Checks to see if a variable
exists. Returns true or false.
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isset($a) |
unset() |
Removes a variable from memory.
|
unset($a) |
empty() |
Checks to see if a variable
contains a non-empty, non-false value.
|
empty($a) |
Like this PHP tutorial? Try our self-paced online
PHP course, which includes videos and
exercises in addition to the content in this PHP tutorial. Not sure if you want
to pay for that? Register for a free demo of the course.
PHP
Operators
Operators
in PHP are similar to those found in many modern C-like programming languages.
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Operator
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Name
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Example
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+ |
Addition
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$a + $b |
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- |
Subtraction
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$a - $b |
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* |
Multiplication
|
$a * $b |
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/ |
Division
|
$a / $b |
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% |
Modulus
|
$a % $b |
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Mathematical Operators
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Operator
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Name
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Example
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. |
Concatenation
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String Operators
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Operator
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Name
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Example
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= |
Assignment
|
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Combination Assignment
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++ |
Increment By One
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-- |
Decrement By One
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Assignment Operators
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Operator
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Name
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Example
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?: |
Ternary
|
$foo = ($age >= 18) ?
'adult' : 'child'; |
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@ |
Error Suppression
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$a = @(1/0); |
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Other Operators
|
||||
Like this PHP tutorial? Try our self-paced
online PHP course, which
includes videos and exercises in addition to the content in this PHP tutorial.
Not sure if you want to pay for that? Register for a free demo of the course.
Creating
Dynamic Pages
Single Quotes vs. Double Quotes
In PHP, for simple strings you
can use single quotes and double quotes interchangeably. However, there is one
important difference of which you need to be aware. Text within single quotes
will not be parsed for variables and escape
sequences
Escape
sequences are used for characters that cannot easily be output within strings.
Common escape sequences are \n for a newline, \t for a tab, \\ for a backslash,
\" for a double quote, and \$ for a dollar sign.
Compare the examples below.
Code Sample:
PhpBasics/Demos/SingleQuotes.php
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<!DOCTYPE HTML><html><head><meta charset="UTF-8"><title>Single Quotes</title></head><body><?php $person = 'George'; echo '\tHello\n$person!!';?></body></html> |
Because of the use of single
quotes above, the string "
\tHello\n$person!!" will be output literally, as shown below.
Code Sample:
PhpBasics/Demos/DoubleQuotes.php
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<!DOCTYPE HTML><html><head><meta charset="UTF-8"><title>Single Quotes</title></head><body><?php $person = "George"; echo "\tHello\n$person!!";?></body></html> |
This
time, because of the double quotes, the string will be parsed for variables and
special characters and will be output as shown below.
To see the effect of the special
characters (
\n and \t), you will have to view the source of the resulting
page.
Passing Variables on the URL
A
common way to pass values from the browser to the server is by appending them to
the URL as follows:
Syntax
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http://www.webucator.com/hello.php?greet=Hello&who=World |
The part of the URL that follows
the question mark is called the query string. One or more name-value pairs can
be passed to the server in this way. Each name-value pair is separated by an
ampersand (
&). The processing page can read
these name-value pairs and use them to determine its response.
The
HTML page below shows an example of how these name-value pairs might be passed.
Code Sample:
PhpBasics/Demos/HelloHi.html
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<!DOCTYPE HTML><html><head><meta charset="UTF-8"><title>Preferred Greeting</title></head><body> Do you prefer a formal greeting or an informal greeting? <ul> <li><a
href="HelloHi.php?greet=Hello">Formal</a></li> <li><a
href="HelloHi.php?greet=Hi">Informal</a></li> <li><a
href="HelloHi.php?greet=Howdy">Friendly</a></li> </ul></body></html> |
Code Sample:
PhpBasics/Demos/HelloHi.php
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<?php //Assign the passed variable to a
variable with //a more convenient name. $greeting = $_GET['greet'];?><!DOCTYPE HTML><html><head><meta charset="UTF-8"><title><?= $greeting ?> World!</title></head><body><?php echo "$greeting World!";?></body></html> |
Notice
the following about the code above.
·
Variable names begin with a
dollar sign (
$).
·
Values passed in the query string
are part of the
$_GET array and can be accessed using the following syntax: $_GET['fieldname'].
·
A shortcut for
echo 'text to print'; is <?= 'text to print' ?>.
Many PHP developers feel that it
is best practice to avoid using this shortcut syntax for
echo. One reason for this is that the shortcut syntax
makes the resulting PHP file impossible to parse as XML. Another is that the
short_open_tag directive must be turned on for it to work. See http://us3.php.net/manual/en/ini.core.php#ini.short-open-tag
Like this PHP tutorial? Try our self-paced
online PHP courses, which
includes videos and exercises in addition to the content in this PHP tutorial.
Not sure if you want to pay for that? Register for a free demo of the course.
Please watch this
video on our YouTube channel to
get a better understanding of variable scope and superglobal variables.
Like this PHP tutorial? Try our self-paced
online PHP course, which
includes videos and exercises in addition to the content in this PHP tutorial.
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