THOUGHTS

**The youth needs to develop an attitude : I can do it! We can do it !! India will do it!!! ""மரங்களை நடுவோம் பசுமை இல்ல விளைவை தடுப்போம்"" !!! PLEASE DO IT**

Wednesday, August 10, 2011

PHP Tutorial




PHP
Introduction
1.    PHP is a powerful tool for making dynamic and interactive Web pages.
2.    PHP is the widely-used, free, and efficient alternative to competitors such as Microsoft's ASP.
3.    In our PHP tutorial you will learn about PHP, and how to execute scripts on your server.
4.    PHP is a server-side scripting language.

What is PHP?

  • PHP stands for PHP: Hypertext Preprocessor
  • PHP is a server-side scripting language, like ASP
  • PHP scripts are executed on the server
  • PHP supports many databases (MySQL, Informix, Oracle, Sybase, Solid, PostgreSQL, Generic ODBC, etc.)
  • PHP is an open source software
  • PHP is free to download and use

What is a PHP File?

  • PHP files can contain text, HTML tags and scripts
  • PHP files are returned to the browser as plain HTML 
  • PHP files have a file extension of ".php", ".php3", or ".phtml"

What is MySQL?

  • MySQL is a database server
  • MySQL is ideal for both small and large applications
  • MySQL supports standard SQL
  • MySQL compiles on a number of platforms
  • MySQL is free to download and use

PHP + MySQL

  • PHP combined with MySQL are cross-platform (you can develop in Windows and serve on a Unix platform)

Why PHP?

  • PHP runs on different platforms (Windows, Linux, Unix, etc.)
  • PHP is compatible with almost all servers used today (Apache, IIS, etc.)
  • PHP is FREE to download from the official PHP resource: www.php.net
  • PHP is easy to learn and runs efficiently on the server side

Where to Start?

To get access to a web server with PHP support, you can:
  • Install Apache (or IIS) on your own server, install PHP, and MySQL
  • Or find a web hosting plan with PHP and MySQL support

PHP Syntax



PHP code is executed on the server, and the plain HTML result is sent to the browser.

Basic PHP Syntax

A PHP scripting block always starts with <?php and ends with ?>. A PHP scripting block can be placed anywhere in the document.
On servers with shorthand support enabled you can start a scripting block with <? and end with ?>.
For maximum compatibility, we recommend that you use the standard form (<?php) rather than the shorthand form.
<?php
?>
A PHP file normally contains HTML tags, just like an HTML file, and some PHP scripting code.
Below, we have an example of a simple PHP script which sends the text "Hello World" to the browser:
<html>
<body>

<?php
echo "Hello World";
?>

</body>
</html>
Each code line in PHP must end with a semicolon. The semicolon is a separator and is used to distinguish one set of instructions from another.
There are two basic statements to output text with PHP: echo and print. In the example above we have used the echo statement to output the text "Hello World".
Note: The file must have the .php extension. If the file has a .html extension, the PHP code will not be executed.

Comments in PHP

In PHP, we use // to make a single-line comment or /* and */ to make a large comment block.
<html>
<body>

<?php
//This is a comment

/*
This is
a comment
block
*/
?>

</body>
</html>

PHP Variables


Variables are used for storing values, such as numbers, strings or function results, so that they can be used many times in a script.

Variables in PHP

Variables are used for storing a values, like text strings, numbers or arrays.
When a variable is set it can be used over and over again in your script
All variables in PHP start with a $ sign symbol.
The correct way of setting a variable in PHP:
$var_name = value;
New PHP programmers often forget the $ sign at the beginning of the variable. In that case it will not work.
Let's try creating a variable with a string, and a variable with a number:
<?php
$txt = "Hello World!";
$number = 16;
?>


No comments:

Post a Comment