Table Of Contents<\/h3>\n\n- 1. Introduction<\/a><\/dt>\n
- \n
\n- 1.1 Where is PHP used?<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 1.2 Why PHP?<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- 2. XAMPP Setup<\/a><\/dt>\n
- 3. PHP Language Basics<\/a><\/dt>\n
- \n
\n- 3.1 Escaping to PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 3.2 Commenting PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 3.3 Hello World<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 3.4 Variables in PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 3.5 Conditional Statements in PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 3.6 Loops in PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- 4. PHP Arrays<\/a><\/dt>\n
- 5. PHP Functions<\/a><\/dt>\n
- 6. Connecting to a Database<\/a><\/dt>\n
- \n
\n- 6.1 Connecting to MySQL Databases<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 6.2 Connecting to MySQLi Databases (Procedurial)<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 6.3 Connecting to MySQLi Databases (Object Oriented)<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 6.4 Connecting to PDO Databases<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- 7. PHP Form Handling<\/a><\/dt>\n
- 8. PHP Include & Require Statements<\/a><\/dt>\n
- 9. Object Oriented Concepts<\/a><\/dt>\n
- \n
\n- 9.1 PHP Classes<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
\n- 9.2 PHP Constructor Function<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- 10. Conclusion<\/a><\/dt>\n
- 11. Download<\/a><\/dt>\n<\/dl>\n<\/div>\n
<\/a>1. Introduction<\/h2>\nBack in 1994, Rasmus Lerdorf unleashed the very first version of PHP. However, now the reference implementation is now produced by The PHP Group. The term PHP originally stood for Personal Home Page<\/em> but now it stands for the recursive acronym: Hypertext Preprocessor<\/em>. PHP 4 and PHP 5 are distributed under the PHP Licence v3.01<\/a>, which is an Open Source<\/strong> licence certified by the Open Source Initiative.<\/p>\n<\/a>1.1 Where is PHP used?<\/h3>\nThree are the main areas where PHP scripts are used:<\/p>\n
\n- \n
\n- Server-side scripting<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
This is the most used and main target for PHP. You need three things to make this work the way you need it. The PHP parser (CGI or server module), a web server and a web browser. You need to run the web server where. You can access the PHP program output with a web browser, viewing the PHP page through the server. All these can run on your home machine if you are just experimenting with PHP programming.<\/p>\n
\n- \n
\n- Command line scripting<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
You can make a PHP script to run it without any server or browser. You only need the PHP parser to use it this way. This type of usage is ideal for scripts regularly executed using cron (on Linux) or Task Scheduler (on Windows). These scripts can also be used for simple text processing tasks.<\/p>\n
\n- \n
\n- Writing desktop applications<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
PHP may not the very best language to create a desktop application with a graphical user interface, but if you know PHP very well, and would like to use some advanced PHP features in your client-side applications you can also use PHP-GTK to write such programs. You also have the ability to write cross-platform applications this way.<\/p>\n
In this article, we’ll have a detailed look at the server-side scripting using PHP.<\/p>\n
<\/a>1.2 Why PHP?<\/h3>\nThere stand convincing arguments for all those who wonder why PHP is so popular today:<\/p>\n
\n- \n
\n- Compatible with almost all servers used nowadays<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
A web server is an information technology that processes requests via HTTP, the basic network protocol used to distribute information on the World Wide Web. There exist many types of web servers that servers use. Some of the most important and well-known are: Apache HTTP Server, IIS (Internet Information Services), lighttpd, Sun Java System Web Server etc. As a matter of fact, PHP is compatible with all these web servers and many more.<\/p>\n
\n- \n
\n- PHP will run on most platforms<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
Unlike some technologies that require a specific operating system or are built specifically for that, PHP is engineered to run on various platforms like Windows, Mac OSX, Linux, Unix etc)<\/p>\n
\n- \n
\n- PHP supports such a wide range of databases<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
An important reason why PHP is so used today is also related to the various databases it supports (is compatible with). Some of these databases are: DB++, dBase, Ingres, Mongo, MaxDB, MongoDB, mSQL, Mssql, MySQL, OCI8, PostgreSQL, SQLite, SQLite3 and so on.<\/p>\n
\n- \n
\n- PHP is free to download and open source<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
Anyone can start using PHP right now by downloading it from php.net<\/a>. Millions of people are using PHP to create dynamic content and database-related applications that make for outstanding web systems. PHP is also open source, which means the original source code is made freely available and may be redistributed and modified.<\/p>\n\n- \n
\n- Easy to learn & large community<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
PHP is a simple language to learn step by step. This makes it easier for people to get engaged in exploring it. It also has such a huge community online that is constantly willing to help you whenever you’re stuck (which actually happens quite a lot).<\/p>\n
The graphic below shows a basic workflow of dynamic content being passed to and from the client using PHP:<\/p>\n![\"PHP](\"http:\/\/www.webcodegeeks.com\/wp-content\/uploads\/2016\/05\/dynamic-php.jpg\")
<\/a>PHP Dynamic Content Interaction<\/figcaption><\/figure>\n<\/a>2. XAMPP Setup<\/h2>\nXAMPP is a free and open source cross-platform web server solution developed by Apache Friends, consisting mainly of the Apache HTTP Server, MariaDB database, and interpreters for scripts written in the PHP and Perl programming languages. In order to make your PHP code execute locally, first install XAMPP.<\/p>\n
\n- \n
\n- Download XAMPP<\/a><\/strong><\/li>\n
- Install the program (check the technologies you want during installation)<\/strong><\/li>\n
- Open XAMPP and click on “Start” on Apache and MySQL (when working with databases)<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
![\"XAMPP](\"http:\/\/www.webcodegeeks.com\/wp-content\/uploads\/2016\/05\/xampp-installed.jpg\")
<\/a>XAMPP window after a successful installation with Apache and MySQL enabled<\/figcaption><\/figure>\n\n- \n
\n- Place your web project inside the
htdocs<\/code> directory. In the common case, if you installed XAMPP directly inside the C: drive of your PC, the path to this folder would be: C:\\xampp\\htdocs<\/code><\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n![\"XAMPP](\"http:\/\/www.webcodegeeks.com\/wp-content\/uploads\/2016\/05\/xampp-directory.jpg\")
<\/a>XAMPP Directory for Web Projects<\/figcaption><\/figure>\nTo test the services are up and running you can just enter localhost<\/strong> in your address bar and expect the welcoming page.<\/p>\n<\/a>3. PHP Language Basics<\/h2>\nThe aim of this section is to introduce the general syntax you should expect in PHP.<\/p>\n
<\/a>3.1 Escaping to PHP<\/h3>\nThere are four ways the PHP parser engine can differentiate PHP code in a webpage:<\/p>\n
\n- \n
\n- Canonical PHP Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
This is the most popular and effective PHP tag style and looks like this:<\/p>\n
<?php...?><\/pre>\n\n- \n
\n- Short-open Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
These are the shortest option, but they might need a bit of configuration, and you might either choose the --enable-short-tags<\/code> configuration option when building PHP, or set the short_open_tag<\/code> setting in your php.ini file.<\/p>\n<?...?><\/pre>\n\n- \n
\n- ASP-like Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
In order to use ASP-like tags, you’ll need to set the configuration option in the php.ini file:<\/p>\n
<%...%><\/pre>\n\n- \n
\n- HTML script Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
You can define a new script with an attribute language like so:<\/p>\n
<script language=\"PHP\">...<\/script><\/pre>\n<\/a>3.2 Commenting PHP<\/h3>\nJust like other languages, there are several ways to comment PHP code. Let’s have a look at the most useful ones:<\/p>\n
\n- \n
\n- Use
#<\/code> to write single-line comments<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n <?\r\n # this is a comment in PHP, a single line comment\r\n ?>\r\n<\/pre>\n
\n- \n
\n- Use
\/\/<\/code> to also write single-line comments<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n <?\r\n \/\/ this is also a comment in PHP, a single line comment\r\n ?>\r\n<\/pre>\n
\n- \n
\n- Use
\/* ... *\/<\/code> to write multi-line comments<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n <?\r\n \/* this is a multi line comment\r\n Name: Web Code Geeks\r\n Type: Website\r\n Purpose: Web Development\r\n *\/\r\n ?>\r\n<\/pre>\n<\/a>3.3 Hello World<\/h3>\nThe very basic example of outputting a text in PHP would be:<\/p>\n
<?\r\n print(\"Hello World\");\r\n echo \"Hello World\";\r\n printf(\"Hello World\");\r\n ?>\r\n<\/pre>\nThe result of the above statements would be the same: “Hello World”. But why are there three different ways to output?<\/p>\n
\n- print<\/strong> returns a value. It always returns 1.<\/li>\n
- echo<\/strong> can take a comma delimited list of arguments to output.<\/li>\n
- printf<\/strong> is a direct analog of C’s
printf()<\/code>.<\/li>\n<\/ul>\n<\/a>3.4 Variables in PHP<\/h3>\nAny type of variable in PHP starts with a leading dollar sign ($) and is assigned a variable type using the = (equals) sign. The value of a variable is the value of its most recent assignment. In PHP, variables do not need to be declared before assignment. The main data types used to construct variables are:<\/p>\n
\n- Integers<\/strong> – whole numbers like 23, 1254, 964 etc<\/li>\n
- Doubles<\/strong> – floating-point numbers like 46.2, 733.21 etc<\/li>\n
- Booleans<\/strong> – only two possible values, true or false<\/li>\n
- Strings<\/strong> – set of characters, like ‘Web Code Geeks’<\/li>\n
- Arrays<\/strong> – named and indexed collections of other values<\/li>\n
- Objects<\/strong> – instances of predefined classes<\/li>\n<\/ul>\n
The following snippet shows all of these data types declared as variables:<\/p>\n
<?\r\n $intNum = 472;\r\n $doubleNum = 29.3;\r\n $boolean = true;\r\n $string = 'Web Code Geeks';\r\n $array = array(\"Pineapple\", \"Grapefruit\", \"Banana\");\r\n\r\n \/\/ creating a class before declaring an object variable\r\n class person {\r\n function agePrint() {\r\n $age = 5;\r\n echo \"This person is $age years old!\";\r\n }\r\n }\r\n \/\/ creating a new object of type person\r\n $object = new person;\r\n ?>\r\n<\/pre>\n<\/a>3.5 Conditional Statements in PHP<\/h3>\nConditional statements are used to execute different code based on different conditions.<\/p>\n
\n- \n
\n- The If statement<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
The if<\/strong> statement executes a piece of code if a condition is true. The syntax is:<\/p>\n if (condition) {\r\n \/\/ code to be executed in case the condition is true\r\n }\r\n<\/pre>\nA practical example would be:<\/p>\n
<?php\r\n $age = 18;\r\n\r\n if ($age < 20) {\r\n echo \"You are a teenager\";\r\n }\r\n ?>\r\n<\/pre>\nBecause the condition is true, the result would be:<\/p>\n
You are a teenager\r\n<\/pre>\n
\n- \n
\n- The If…Else statement<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
- \n
- 1.1 Where is PHP used?<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 1.2 Why PHP?<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- 2. XAMPP Setup<\/a><\/dt>\n
- 3. PHP Language Basics<\/a><\/dt>\n
- \n
- \n
- 3.1 Escaping to PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 3.2 Commenting PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 3.3 Hello World<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 3.4 Variables in PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 3.5 Conditional Statements in PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 3.6 Loops in PHP<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- 4. PHP Arrays<\/a><\/dt>\n
- 5. PHP Functions<\/a><\/dt>\n
- 6. Connecting to a Database<\/a><\/dt>\n
- \n
- \n
- 6.1 Connecting to MySQL Databases<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 6.2 Connecting to MySQLi Databases (Procedurial)<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 6.3 Connecting to MySQLi Databases (Object Oriented)<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 6.4 Connecting to PDO Databases<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- 7. PHP Form Handling<\/a><\/dt>\n
- 8. PHP Include & Require Statements<\/a><\/dt>\n
- 9. Object Oriented Concepts<\/a><\/dt>\n
- \n
- \n
- 9.1 PHP Classes<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- \n
- \n
- 9.2 PHP Constructor Function<\/a><\/dt>\n<\/dl>\n<\/dd>\n
- 10. Conclusion<\/a><\/dt>\n
- 11. Download<\/a><\/dt>\n<\/dl>\n<\/div>\n
<\/a>1. Introduction<\/h2>\n
Back in 1994, Rasmus Lerdorf unleashed the very first version of PHP. However, now the reference implementation is now produced by The PHP Group. The term PHP originally stood for Personal Home Page<\/em> but now it stands for the recursive acronym: Hypertext Preprocessor<\/em>. PHP 4 and PHP 5 are distributed under the PHP Licence v3.01<\/a>, which is an Open Source<\/strong> licence certified by the Open Source Initiative.<\/p>\n
<\/a>1.1 Where is PHP used?<\/h3>\n
Three are the main areas where PHP scripts are used:<\/p>\n
- \n
- \n
- \n
- Server-side scripting<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
This is the most used and main target for PHP. You need three things to make this work the way you need it. The PHP parser (CGI or server module), a web server and a web browser. You need to run the web server where. You can access the PHP program output with a web browser, viewing the PHP page through the server. All these can run on your home machine if you are just experimenting with PHP programming.<\/p>\n
- \n
- \n
- \n
- Command line scripting<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
You can make a PHP script to run it without any server or browser. You only need the PHP parser to use it this way. This type of usage is ideal for scripts regularly executed using cron (on Linux) or Task Scheduler (on Windows). These scripts can also be used for simple text processing tasks.<\/p>\n
- \n
- \n
- \n
- Writing desktop applications<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
PHP may not the very best language to create a desktop application with a graphical user interface, but if you know PHP very well, and would like to use some advanced PHP features in your client-side applications you can also use PHP-GTK to write such programs. You also have the ability to write cross-platform applications this way.<\/p>\n
In this article, we’ll have a detailed look at the server-side scripting using PHP.<\/p>\n
<\/a>1.2 Why PHP?<\/h3>\n
There stand convincing arguments for all those who wonder why PHP is so popular today:<\/p>\n
- \n
- \n
- \n
- Compatible with almost all servers used nowadays<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
A web server is an information technology that processes requests via HTTP, the basic network protocol used to distribute information on the World Wide Web. There exist many types of web servers that servers use. Some of the most important and well-known are: Apache HTTP Server, IIS (Internet Information Services), lighttpd, Sun Java System Web Server etc. As a matter of fact, PHP is compatible with all these web servers and many more.<\/p>\n
- \n
- \n
- \n
- PHP will run on most platforms<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
Unlike some technologies that require a specific operating system or are built specifically for that, PHP is engineered to run on various platforms like Windows, Mac OSX, Linux, Unix etc)<\/p>\n
- \n
- \n
- \n
- PHP supports such a wide range of databases<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
An important reason why PHP is so used today is also related to the various databases it supports (is compatible with). Some of these databases are: DB++, dBase, Ingres, Mongo, MaxDB, MongoDB, mSQL, Mssql, MySQL, OCI8, PostgreSQL, SQLite, SQLite3 and so on.<\/p>\n
- \n
- \n
- \n
- PHP is free to download and open source<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
Anyone can start using PHP right now by downloading it from php.net<\/a>. Millions of people are using PHP to create dynamic content and database-related applications that make for outstanding web systems. PHP is also open source, which means the original source code is made freely available and may be redistributed and modified.<\/p>\n
- \n
- \n
- \n
- Easy to learn & large community<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
PHP is a simple language to learn step by step. This makes it easier for people to get engaged in exploring it. It also has such a huge community online that is constantly willing to help you whenever you’re stuck (which actually happens quite a lot).<\/p>\n
The graphic below shows a basic workflow of dynamic content being passed to and from the client using PHP:<\/p>\n
<\/a>PHP Dynamic Content Interaction<\/figcaption><\/figure>\n <\/a>2. XAMPP Setup<\/h2>\n
XAMPP is a free and open source cross-platform web server solution developed by Apache Friends, consisting mainly of the Apache HTTP Server, MariaDB database, and interpreters for scripts written in the PHP and Perl programming languages. In order to make your PHP code execute locally, first install XAMPP.<\/p>\n
- \n
- \n
- \n
- Download XAMPP<\/a><\/strong><\/li>\n
- Install the program (check the technologies you want during installation)<\/strong><\/li>\n
- Open XAMPP and click on “Start” on Apache and MySQL (when working with databases)<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
<\/a>XAMPP window after a successful installation with Apache and MySQL enabled<\/figcaption><\/figure>\n - \n
- \n
- \n
- Place your web project inside the
htdocs<\/code> directory. In the common case, if you installed XAMPP directly inside the C: drive of your PC, the path to this folder would be:C:\\xampp\\htdocs<\/code><\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n<\/a>XAMPP Directory for Web Projects<\/figcaption><\/figure>\n To test the services are up and running you can just enter localhost<\/strong> in your address bar and expect the welcoming page.<\/p>\n
<\/a>3. PHP Language Basics<\/h2>\n
The aim of this section is to introduce the general syntax you should expect in PHP.<\/p>\n
<\/a>3.1 Escaping to PHP<\/h3>\n
There are four ways the PHP parser engine can differentiate PHP code in a webpage:<\/p>\n
- \n
- \n
- \n
- Canonical PHP Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
This is the most popular and effective PHP tag style and looks like this:<\/p>\n
<?php...?><\/pre>\n
- \n
- \n
- \n
- Short-open Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
These are the shortest option, but they might need a bit of configuration, and you might either choose the
--enable-short-tags<\/code> configuration option when building PHP, or set theshort_open_tag<\/code> setting in your php.ini file.<\/p>\n<?...?><\/pre>\n
- \n
- \n
- \n
- ASP-like Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
In order to use ASP-like tags, you’ll need to set the configuration option in the php.ini file:<\/p>\n
<%...%><\/pre>\n
- \n
- \n
- \n
- HTML script Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
You can define a new script with an attribute language like so:<\/p>\n
<script language=\"PHP\">...<\/script><\/pre>\n
<\/a>3.2 Commenting PHP<\/h3>\n
Just like other languages, there are several ways to comment PHP code. Let’s have a look at the most useful ones:<\/p>\n
- \n
- \n
- \n
- Use
#<\/code> to write single-line comments<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<?\r\n # this is a comment in PHP, a single line comment\r\n ?>\r\n<\/pre>\n
- \n
- \n
- \n
- Use
\/\/<\/code> to also write single-line comments<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<?\r\n \/\/ this is also a comment in PHP, a single line comment\r\n ?>\r\n<\/pre>\n
- \n
- \n
- \n
- Use
\/* ... *\/<\/code> to write multi-line comments<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<?\r\n \/* this is a multi line comment\r\n Name: Web Code Geeks\r\n Type: Website\r\n Purpose: Web Development\r\n *\/\r\n ?>\r\n<\/pre>\n
<\/a>3.3 Hello World<\/h3>\n
The very basic example of outputting a text in PHP would be:<\/p>\n
<?\r\n print(\"Hello World\");\r\n echo \"Hello World\";\r\n printf(\"Hello World\");\r\n ?>\r\n<\/pre>\n
The result of the above statements would be the same: “Hello World”. But why are there three different ways to output?<\/p>\n
- \n
- print<\/strong> returns a value. It always returns 1.<\/li>\n
- echo<\/strong> can take a comma delimited list of arguments to output.<\/li>\n
- printf<\/strong> is a direct analog of C’s
printf()<\/code>.<\/li>\n<\/ul>\n<\/a>3.4 Variables in PHP<\/h3>\n
Any type of variable in PHP starts with a leading dollar sign ($) and is assigned a variable type using the = (equals) sign. The value of a variable is the value of its most recent assignment. In PHP, variables do not need to be declared before assignment. The main data types used to construct variables are:<\/p>\n
- \n
- Integers<\/strong> – whole numbers like 23, 1254, 964 etc<\/li>\n
- Doubles<\/strong> – floating-point numbers like 46.2, 733.21 etc<\/li>\n
- Booleans<\/strong> – only two possible values, true or false<\/li>\n
- Strings<\/strong> – set of characters, like ‘Web Code Geeks’<\/li>\n
- Arrays<\/strong> – named and indexed collections of other values<\/li>\n
- Objects<\/strong> – instances of predefined classes<\/li>\n<\/ul>\n
The following snippet shows all of these data types declared as variables:<\/p>\n
<?\r\n $intNum = 472;\r\n $doubleNum = 29.3;\r\n $boolean = true;\r\n $string = 'Web Code Geeks';\r\n $array = array(\"Pineapple\", \"Grapefruit\", \"Banana\");\r\n\r\n \/\/ creating a class before declaring an object variable\r\n class person {\r\n function agePrint() {\r\n $age = 5;\r\n echo \"This person is $age years old!\";\r\n }\r\n }\r\n \/\/ creating a new object of type person\r\n $object = new person;\r\n ?>\r\n<\/pre>\n<\/a>3.5 Conditional Statements in PHP<\/h3>\n
Conditional statements are used to execute different code based on different conditions.<\/p>\n
- \n
- \n
- \n
- The If statement<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
The if<\/strong> statement executes a piece of code if a condition is true. The syntax is:<\/p>\n
if (condition) {\r\n \/\/ code to be executed in case the condition is true\r\n }\r\n<\/pre>\nA practical example would be:<\/p>\n
<?php\r\n $age = 18;\r\n\r\n if ($age < 20) {\r\n echo \"You are a teenager\";\r\n }\r\n ?>\r\n<\/pre>\nBecause the condition is true, the result would be:<\/p>\n
You are a teenager\r\n<\/pre>\n
- \n
- \n
- \n
- The If…Else statement<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
- \n
- The If statement<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
- Doubles<\/strong> – floating-point numbers like 46.2, 733.21 etc<\/li>\n
- echo<\/strong> can take a comma delimited list of arguments to output.<\/li>\n
- print<\/strong> returns a value. It always returns 1.<\/li>\n
- Use
- \n
- Use
- \n
- Use
- \n
- HTML script Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
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- ASP-like Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
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- Short-open Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
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- Canonical PHP Tags<\/strong><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n
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- Place your web project inside the
- Install the program (check the technologies you want during installation)<\/strong><\/li>\n
- Download XAMPP<\/a><\/strong><\/li>\n
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- Easy to learn & large community<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
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- PHP is free to download and open source<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
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- PHP supports such a wide range of databases<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
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- PHP will run on most platforms<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
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- Compatible with almost all servers used nowadays<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
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- Writing desktop applications<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
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- Command line scripting<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
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- Server-side scripting<\/strong><\/li>\n<\/ul>\n<\/li>\n<\/ul>\n
- 10. Conclusion<\/a><\/dt>\n
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- 7. PHP Form Handling<\/a><\/dt>\n
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- 4. PHP Arrays<\/a><\/dt>\n
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- \n
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- 2. XAMPP Setup<\/a><\/dt>\n
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