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<?php include('server.php') ?>
<!DOCTYPE html>
<html lang="en">
<head>
<!-- Required meta tags -->
<meta charset="utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no" />
<script defer src="https://use.fontawesome.com/releases/v5.0.7/js/all.js"></script>
<link rel="stylesheet" href="styles.css">
<script>
function openSlideMenu(){
document.getElementById('menu').style.width = '250px';
document.getElementById('content').style.marginLeft = '250px';
}
function closeSlideMenu(){
document.getElementById('menu').style.width = '0';
document.getElementById('content').style.marginLeft = '0';
}
</script>
<!-- Bootstrap CSS -->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.0/css/bootstrap.min.css"
integrity="sha384-9aIt2nRpC12Uk9gS9baDl411NQApFmC26EwAOH8WgZl5MYYxFfc+NcPb1dKGj7Sk" crossorigin="anonymous" />
<title>TANT SCHOOL</title>
<style>
</style>
</head>
<body>
<header>
<nav class="navbar navbar-expand-lg navbar-dark bg-primary" style="background-image: linear-gradient(to top, rgba(190, 45, 219, 0.733), rgb(240, 66, 225));">
<a class="navbar-brand" href="index.php">TantSchool</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent"
aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarSupportedContent">
<ul class="navbar-nav mr-auto">
<li class="nav-item">
<a class="nav-link" href="index.php">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item active">
<a class="nav-link" href="courses.php">Courses</a>
</li>
<li class="nav-item">
<a class="nav-link" href="exercises.php">Practice Exercises</a>
</li>
<li class="nav-item">
<a class="nav-link" href="about.php">About Us</a>
</li>
<li class="nav-item">
<a class="nav-link" href="contactus.php">Contact Us</a>
</li>
</ul>
<?php if (isset($_SESSION['username'])) : ?>
<a href="userprofile.php">
<p style="color: white;">Welcome <strong><?php echo $_SESSION['username']; ?></strong></p></a>
<a href="exercises.php?logout='1'" class="btn btn-info transition-hover btn-lg ml-3">Logout</a>
<?php else: ?>
<form class="form-inline my-2 my-lg-0">
<a href="login.php" class="btn btn-primary transition-hover btn-lg ml-3">Sign In</a>
<a href="register.php" class="btn btn-success transition-hover btn-lg ml-3">Sign Up</a>
</button>
</form>
<?php endif ?>
</div>
</nav>
<div id="content">
<span class="slide">
<a href="#" onclick="openSlideMenu()">
<i class="fas fa-bars"></i>
</a>
</span>
<div id="menu" class="nav">
<a href="#" class="close" onclick="closeSlideMenu()">
<i class="fas fa-times"></i>
</a>
<h4 style="color: white;margin-left:33px;">PHP Tutorials</h4>
<a class="nav-link" href="#intro">PHP Intro</a>
<a class="nav-link" href="#syntax">PHP Syntax</a>
<!-- <a class="nav-link" href="#comments">PHP Comments</a> -->
<a class="nav-link" href="#variables">PHP Variables</a>
<a class="nav-link" href="#echo">PHP Echo/Print</a>
<a class="nav-link" href="#data">PHP Data Types</a>
<a class="nav-link" href="#switch">PHP Switch</a>
<a class="nav-link" href="#ifelse">PHP if...else...elseif</a>
<a class="nav-link" href="#loop">PHP Loop</a>
<a class="nav-link" href="#functions">PHP Function</a>
<a class="nav-link" href="#arrays">PHP Arrays</a>
<a class="nav-link" href="#superglobal">PHP Super globals</a>
<a class="nav-link" href="#regex">PHP RegEx</a>
</div>
</div>
<div class="container">
<div id="intro">
<h1>PHP: Hypertext Preprocessor <span class="color_h1">Introduction</span></h1>
<hr>
<iframe width="90%" height="315" src="https://youtube.com/embed/a_qREkJ78f4" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
<br><br>
<h2>What You Should Already Know</h2>
<p>Before you continue you should have a basic understanding of the following:</p>
<ul>
<li>HTML</li>
<li>CSS</li>
<li>JavaScript</li>
</ul>
<p>If you want to study these subjects first, find the tutorials on our <a href="courses.php">Home page.</a></p>
<h2>What is PHP?</h2>
<ul>
<li>PHP is an acronym for "PHP: Hypertext Preprocessor"</li>
<li>PHP is a widely-used, open source scripting language</li>
<li>PHP scripts are executed on the server</li>
<li>PHP is free to download and use</li>
</ul>
<div style="width:100%;">
<br><br>
<div style="margin-left:2%;">
<strong><p>PHP is an amazing and popular language!</p></strong>
<p>It is powerful enough to be at the core of the
biggest blogging system on the web (WordPress)!</p>
<p>It is deep enough to run the largest social network (Facebook)!</p>
<p>It is also easy enough to be a beginner's first server side language!</p>
<br><br>
</div>
</div>
<br>
<h2>What is PHP File?</h2>
<ul>
<li>PHP files can contain text, HTML, CSS, JavaScript, and PHP code</li>
<li>PHP code is executed on the server, and the result is returned to the browser as plain HTML</li>
<li>PHP files have extension ".php"</li>
</ul>
<h3>What Can PHP Do?</h3>
<ul>
<li>PHP can generate dynamic page content</li>
<li>PHP can create, open, read, write, delete, and close files on the server</li>
<li>PHP can collect form data</li>
<li>PHP can send and receive cookies</li>
<li>PHP can add, delete, modify data in your database</li>
<li>PHP can be used to control user-access</li>
<li>PHP can encrypt data</li>
<li></li>
<li></li>
</ul>
<p>With PHP you are not limited to output HTML. You can output images, PDF files, and even Flash movies.
You can also output any text, such as XHTML and XML.</p>
<h3>Why PHP?</h3>
<ul>
<li>PHP runs on various platforms (Windows, Linux, Unix, Mac OS X, etc.)</li>
<li>PHP is compatible with almost all servers used today (Apache, IIS, etc.)</li>
<li>PHP supports a wide range of databases</li>
<li>PHP is easy to learn and runs efficiently on the server side</li>
</ul>
<h3>What's New In PHP 7</h3>
<ul>
<li>PHP 7 is much faster than the previous popular stable release (PHP 5.6)</li>
<li>PHP 7 has improved Error Handling</li>
<li>PHP 7 supports stricter Type Declarations for function arguments</li>
<li>PHP 7 supports new operators (like the spaceship operator: <=> )</li>
</ul>
<hr>
</div>
<div id="syntax">
<h1>PHP <span class="color_h1">Syntax</span></h1>
<hr>
<iframe width="90%" height="315" src="https://www.youtube.com/embed/eLBDf7U4DfQ" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
<hr>
</div>
<div id="indent">
<h1>Basic PHP <span class="color_h1">Syntax</span></h1>
<hr>
<p>A PHP script can be placed anywhere in the document.</p>
<p>A PHP script starts with <?php and ends with ?></p>
<div style="border:1px solid black;width:100%">
<p>
<br>
<?php<br>
// PHP code goes here<br>
?>
</p>
</div>
<p>A PHP file normally contains HTML tags, and some PHP scripting code.</p>
<p>Below, we have an example of a simple PHP file, with a PHP script that uses a
built-in PHP function "echo" to output the text "Hello World!" on a web page:</p>
<div class="w3-example">
<h3>Example</h3>
<div style="background-color:white;">
<br>
<div class="w3-code htmlHigh notranslate">
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>!DOCTYPE<span class="attributecolor" style="color:red"> html</span><span class="tagcolor" style="color:mediumblue">></span></span><br>
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>html<span class="tagcolor" style="color:mediumblue">></span></span><br>
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>body<span class="tagcolor" style="color:mediumblue">></span></span><br><br>
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>h1<span class="tagcolor" style="color:mediumblue">></span></span>My first PHP page<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>/h1<span class="tagcolor" style="color:mediumblue">></span></span><br><br>
<span class="phpcolor" style="color:black"><span class="phptagcolor" style="color:red"><?php</span><br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"Hello World!"</span>;<br><span class="phptagcolor" style="color:red">?></span></span><br><br>
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>/body<span class="tagcolor" style="color:mediumblue">></span></span><br>
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>/html<span class="tagcolor" style="color:mediumblue">></span></span>
<br><br>
</div>
</div>
<div>
</div>
<br>
<h3>PHP Case Sensitivity</h3>
<p>In PHP, keywords (e.g. if, else, while, echo, etc.), classes,
functions, and user-defined functions are not case-sensitive.</p>
<p>In the example below, all three echo statements below are equal and legal:</p>
<div class="w3-example">
<h3>Example</h3>
<div style="background-color:white;">
<br>
<div class="w3-code htmlHigh notranslate">
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>!DOCTYPE<span class="attributecolor" style="color:red"> html</span><span class="tagcolor" style="color:mediumblue">></span></span><br>
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>html<span class="tagcolor" style="color:mediumblue">></span></span><br>
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>body<span class="tagcolor" style="color:mediumblue">></span></span><br><br>
<span class="phpcolor" style="color:black"><span class="phptagcolor" style="color:red"><?php</span><br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">ECHO</span> <span class="phpstringcolor" style="color:brown">"Hello World!<br>"</span>;<br><span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"Hello World!<br>"</span>;<br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">EcHo</span> <span class="phpstringcolor" style="color:brown">"Hello World!<br>"</span>;<br><span class="phptagcolor" style="color:red">?></span></span><br><br>
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>/body<span class="tagcolor" style="color:mediumblue">></span></span><br>
<span class="tagnamecolor" style="color:brown"><span class="tagcolor" style="color:mediumblue"><</span>/html<span class="tagcolor" style="color:mediumblue">></span></span>
<br><br>
</div>
</div>
</div>
<br>
<div style="width:100%;">
<br>
<div style="margin-left:2%;">
<strong><p>NOTE:</p></strong>
<p>However; all variable names are case-sensitive!</p>
<br>
</div>
</div>
<hr>
<div id="variables">
<h1>PHP <span class="color_h1">Variables</span></h1>
<hr>
<iframe width="90%" height="315" src="https://www.youtube.com/embed/L2kwYV_paRE" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
<br><br>
<p>Variables are "containers" for storing information.</p>
<hr>
<h2>Creating (Declaring) PHP Variables</h2>
<p>In PHP, a variable starts with the $ sign, followed by the name of the variable:</p>
<div class="w3-example">
<h3>Example</h3>
<div style="background-color:white;">
<br>
<div class="w3-code notranslate htmlHigh">
<span class="phpcolor" style="color:black"><span class="phptagcolor" style="color:red"><?php</span><br>
$txt = <span class="phpstringcolor" style="color:brown">"Hello world!"</span>;<br>
$x = <span class="phpnumbercolor" style="color:red">5</span>;<br>$y = <span class="phpnumbercolor" style="color:red">10.5</span>;<br>
<span class="phptagcolor" style="color:red">?></span></span>
<br><br>
</div>
</div>
</div>
<p>After the execution of the statements above, the variable $txt will
hold the value Hello world!, the variable $x will hold the value 5, and the variable $y will hold the value 10.5.</p>
<strong><p>NOTE:</p></strong>
<li>When you assign a text value to a variable, put quotes around the value.</li>
<li>Unlike other programming languages, PHP has no command for declaring a variable.
It is created the moment you first assign a value to it.</li>
<br>
<div style="width:100%;">
<br>
<div style="margin-left:2%;">
<p>Think of variables as containers for storing data.</p>
<br>
</div>
</div>
<br>
<h3>PHP Variables</h3>
<p>A variable can have a short name (like x and y) or a more descriptive name (age, carname, total_volume).<br>
Rules for PHP variables:</p>
<ul>
<li>A variable starts with the $ sign, followed by the name of the variable</li>
<li>A variable name must start with a letter or the underscore character</li>
<li>A variable name cannot start with a number</li>
<li>A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ )</li>
<li>Variable names are case-sensitive (age, Age and AGE are three different variables)</li>
</ul>
<br>
<div style="width:100%;">
<br>
<div style="margin-left:2%;">
<p>Remember that PHP variable names are case-sensitive!</p>
<br>
</div>
</div>
<br>
<h3>PHP Variables Scope</h3>
In PHP, variables can be declared anywhere in the script.
The scope of a variable is the part of the script where the variable can be referenced/used.
PHP has three different variable scopes:
<li>local</li>
<li>global</li>
<li>static</li>
<br>
<h3>Global Scope</h3>
<br>
A variable declared <strong>outside</strong> a function has a GLOBAL SCOPE and can only be accessed outside a function:
<br>
<br>
<div class="w3-example">
<h3>Example</h3>
<div style="background-color:white;">
<br>
<p>Variable with global scope: </p>
<div class="w3-code htmlHigh notranslate">
<span class="phpcolor" style="color:black"><span class="phptagcolor" style="color:red"><?php</span><br>$x = <span class="phpnumbercolor" style="color:red">5</span>; <span class="commentcolor" style="color:green">// global scope<br></span><br><span class="phpkeywordcolor" style="color:mediumblue">function</span> myTest() {<br> <span class="commentcolor" style="color:green">// using x inside this function will generate an error<br></span> <span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"<p>Variable x inside function is: $x</p>"</span>;<br>} <br>myTest();<br><br><span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"<p>Variable x outside function is: $x</p>"</span>;<br><span class="phptagcolor" style="color:red">?></span></span>
<br><br>
</div>
</div>
</div>
<br>
<h3>Local Scope</h3>
<br>
A variable declared <strong>within</strong> a function has a LOCAL SCOPE and can only be accessed outside a function:
<br>
<br>
<div class="w3-example">
<h3>Example</h3>
<div style="background-color:white;">
<br>
<p>Variable with local scope: </p>
<div class="w3-code htmlHigh notranslate">
<span class="phpcolor" style="color:black"><span class="phptagcolor" style="color:red"><?php</span><br>$x = <span class="phpnumbercolor" style="color:red">5</span>; <span class="commentcolor" style="color:green">// global scope<br></span><br><span class="phpkeywordcolor" style="color:mediumblue">function</span> myTest() {<br> <span class="commentcolor" style="color:green">// using x inside this function will generate an error<br></span> <span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"<p>Variable x inside function is: $x</p>"</span>;<br>} <br>myTest();<br><br><span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"<p>Variable x outside function is: $x</p>"</span>;<br><span class="phptagcolor" style="color:red">?></span></span>
<br><br>
</div>
</div>
</div>
<br>
<h3>Static Keyword</h3>
<br>
Normally, when a function is completed/executed, all of its variables are deleted.
However, sometimes we want a local variable NOT to be deleted. We need it for a further job.
<br>
To do this, use the static keyword when you first declare the variable:
<br>
<br>
<div class="w3-example">
<h3>Example</h3>
<div style="background-color:white;">
<br>
<div class="w3-code htmlHigh notranslate">
<span class="phpcolor" style="color:black"><span class="phptagcolor" style="color:red"><?php</span><br><span class="phpkeywordcolor" style="color:mediumblue">function</span> myTest()<span class="phpnumbercolor" style="color:red">
</span>{<br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">static</span> $x = <span class="phpnumbercolor" style="color:red">0</span>;<br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">echo</span> $x;<br><span class="phpnumbercolor" style="color:red">
</span> $x++;<br><span class="phpnumbercolor" style="color:red">
</span>}<br><br>
myTest();<br>
myTest();<br>
myTest();<br><span class="phptagcolor" style="color:red">?></span></span>
<br><br>
</div>
</div>
</div>
<hr>
<div id="echo">
<h1>PHP <span class="color_h1">Echo / Print Statement</span></h1>
<hr>
<iframe width="90%" height="315" src="https://www.youtube.com/embed/V9c2M7c5xqU" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
<br><br>
<p>With PHP, there are two basic ways to get output: echo and print.
<br>
In this tutorial we use echo or print in almost every example.
<br>So, this chapter contains a little more info about those two output statements.</p>
<h3>The PHP echo Statement</h3>
<p>The echo statement can be used with or without parentheses: echo or echo().
<br>The following example shows how to output text with the echo command (notice that the text can contain HTML markup):</p>
<div class="w3-example">
<h3>Example</h3>
<div style="background-color:white;">
<br>
<div class="w3-code htmlHigh notranslate">
<span class="phpcolor" style="color:black"><span class="phptagcolor" style="color:red"><?php</span><br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"<h2>PHP is Fun!</h2>"</span>;<br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"Hello world!<br>"</span>;<br><span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"I'm about to learn PHP!<br>"</span>;<br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor" style="color:brown">"This "</span>, <span class="phpstringcolor" style="color:brown">"string "</span>, <span class="phpstringcolor" style="color:brown">"was "</span>, <span class="phpstringcolor" style="color:brown">"made "</span>, <span class="phpstringcolor" style="color:brown">"with multiple parameters."</span>;<br>
<span class="phptagcolor" style="color:red">?></span></span>
<br><br>
</div>
</div>
</div>
<br>
<h3>The PHP print Statement</h3>
<p>The print statement can be used with or without parentheses: print or ptint().
<br>The following example shows how to output text with the print command (notice that the text can contain HTML markup):</p>
<div class="w3-example">
<h3>Example</h3>
<div style="background-color:white;">
<br>
<div class="w3-code htmlHigh notranslate">
<span class="phpcolor" style="color:black"><span class="phptagcolor" style="color:red"><?php</span><br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">print</span> <span class="phpstringcolor" style="color:brown">"<h2>PHP is Fun!</h2>"</span>;<br><span class="phpnumbercolor" style="color:red">
</span> <span class="phpkeywordcolor" style="color:mediumblue">print</span> <span class="phpstringcolor" style="color:brown">"Hello world!<br>"</span>;<br><span class="phpkeywordcolor" style="color:mediumblue">print</span> <span class="phpstringcolor" style="color:brown">"I'm about to learn PHP!"</span>;<br>
<span class="phptagcolor" style="color:red">?></span></span>
<br><br>
</div>
</div>
</div>
</div>
<div>
<hr>
<div id="data">
<h1>PHP <span class="color_h1">Data Types</span></h1>
<hr>
<iframe width="90%" height="315" src="https://www.youtube.com/embed/oXX2SJKijig" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
<br>
<h2>PHP Built-in Data Types</h2>
<p>Variables can store data of different types, and different data types can do different things.
<br>
PHP supports the following data types:</p>
<ul>
<li>String</li>
<li>Integer</li>
<li>Float</li>
<li>Boolean</li>
<li>Array</li>
<li>Object</li>
<li>Null</li>
<li>Resource</li>
</ul>
<h3>PHP String</h3>
<p>A string is a sequence of characters, like "Hello world!".
<br>
A string can be any text inside quotes. You can use single or double quotes:</p>
<div class="w3-example">
<h3>Example</h3>
<div style="background-color:white;">
<br>
<div class="w3-code htmlHigh notranslate">
<span class="phpcolor" style="color:black"><span class="phptagcolor" style="color:red"><?php</span> <br>$x =
<span class="phpstringcolor" style="color:brown">"Hello world!"</span>;<br>$y = <span class="phpstringcolor"
style="color:brown">'Hello world!'</span>;<br><br><span class="phpkeywordcolor" style="color:mediumblue">echo
</span> $x;<br><span class="phpkeywordcolor" style="color:mediumblue">echo</span> <span class="phpstringcolor"
style="color:brown">"<br>"</span>; <br><span class="phpkeywordcolor" style="color:mediumblue">echo</span>
$y;<br><span class="phptagcolor" style="color:red">?></span></span> </div>
<br><br>
</div>
</div>
</div>
<br>
<h3>PHP Integer</h3>
<p>A string is a sequence of characters, like "Hello world!".
<br>