and is a powerful tool for making dynamic and interactive Web pages quickly. PHP is a widely-used, open source PHP is a widely-used, open source scripting language PHP scripts are executed on the server PHP costs nothing, it is free to download and use
(Windows, Linux, Unix, Mac OS X, etc.) PHP is compatible with almost all servers used today (Apache, IIS, etc.) PHP supports a wide range of databases PHP supports a wide range of databases PHP is easy to learn and runs efficiently on the server side It is powerful enough to be at the core of the biggest blogging system on the web (WordPress)! It is deep enough to run the largest social network (Facebook)!
read, write, delete, and close files on the server Send and receive cookies Send and receive cookies Add, delete, modify data in your database Encrypt data Output images, PDF files, and even Flash movies
web server (Apache) Install PHP Install a database, such as MySQL Install a database, such as MySQL Example: XAMPP (Apache + MySQL + PHP + Perl) XAMPP is the most popular PHP development environment
A variable starts with the $ sign, followed by the name of the variable A variable name must start with a letter or A variable name must start with a letter or the underscore character A variable name cannot start with a number A variable name can only contain alpha- numeric characters and underscores (A-z, 0-9, and _ ) Variable names are case sensitive ($y and $Y are two different variables)
two basic ways to get output: echo and print. There are some differences between echo and print: print: echo - can output one or more strings print - can only output one string, and returns always 1 Example:
conditional statements: if statement - executes some code only if a specified condition is true condition is true if...else statement - executes some code if a condition is true and another code if the condition is false if...elseif....else statement - selects one of several blocks of code to be executed switch statement - selects one of many blocks of code to be executed
statements: while - loops through a block of code as long as the specified condition is true specified condition is true do...while - loops through a block of code once, and then repeats the loop as long as the 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
that can be used repeatedly in a program. A function will not execute immediately when a page loads. page loads. A function will be executed by a call to the function.
- sort arrays in ascending order rsort() - sort arrays in descending order asort() - sort associative arrays in ascending order, asort() - sort associative arrays in ascending order, according to the value ksort() - sort associative arrays in ascending order, according to the key arsort() - sort associative arrays in descending order, according to the value krsort() - sort associative arrays in descending order, according to the key
of PHP is the way it handles HTML forms. The basic concept that is important to understand is that any form element will automatically be available to your PHP scripts. that any form element will automatically be available to your PHP scripts. The PHP $_GET and $_POST are used to collect form-data.
an array (e.g. array( key => value, key2 => value2, key3 => value3, ...)). This array holds key/value pairs, where keys are the names of the form controls and values are the input data from the user. data from the user. When to use GET? Information sent from a form with the GET method is visible to everyone facebook.com?welcome.php?name=Mohamed When to use POST? Information sent from a form with the POST method is invisible to others facebook.com?welcome.php