Summary
Abstract Classes
Using PHP, you will be able to create abstract classes. These classes cannot be instantiated. Methods can also be abstract. But you should keep in mind that a class using an abstract method, must be abstract too.
Access Modifiers
Access modifiers control the way classes and methods can be accessed to. There are 3 access modifiers :
- Public
- Protected
- Private
AJAX
AJAX (Asynchronous JavaScript and XML) has been used a for a long period of time now, in order to create and update dynamically parts of/or entire Web pages.
AJAX Search
Example of Ajax search script :
<html>
<head>
<script>
function showHint(str) {
if (str.length == 0) {
document.getElementById("txtHint").innerHTML = "";
return;
} else {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
document.getElementById("txtHint").innerHTML = xmlhttp.responseText;
}
}
xmlhttp.open("GET", "ajax-search-main.php?q=" + str, true);
xmlhttp.send();
}
}
</script>
</head>
<body>
<p><b>Search for the latest news. Please enter a subject (ChatGPT, Climate change, Russian invasion of Ukraine) :</b><br>
<form>
<input type = "text" onkeyup = "showHint(this.value)">
</form>
<br>Entered Subject: <span id="txtHint"></span></br>
</body>
</html>
Ajax script engine (GET method) :
<?php
$a[] = "ChatGPT";
$a[] = "Climate change";
$a[] = "Russian invasion of Ukraine";
$q = $_REQUEST["q"];
$hint = "";
if ($q !== "") {
$q = strtolower($q);
$len = strlen($q);
foreach($a as $name) {
if (stristr($q, substr($name, 0, $len))) {
if ($hint === "") {
$hint = $name;
} else {
$hint .= ", $name";
}
}
}
}
echo $hint === "" ? "Please enter a valid subject name" : $hint;
?>
AJAX Auto Complete and Live Search
AJAX Autocompletion fluidify the search process, using for example XML.
<html>
<head>
<style>
div {
width: 288px;
color: black;
}
</style>
<script>
function showResult(str) {
if (str.length == 0) {
document.getElementById("ajax-autocomplete-main").innerHTML = "";
document.getElementById("ajax-autocomplete-main").style.border = "0px";
return;
}
if (window.XMLHttpRequest) {
xmlhttp = new XMLHttpRequest();
} else {
xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
}
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
document.getElementById("ajax-autocomplete-main").innerHTML = xmlhttp.responseText;
document.getElementById("ajax-autocomplete-main").style.border = "1px solid #000000";
}
}
xmlhttp.open("GET","ajax-autocomplete-main.php?q="+str,true);
xmlhttp.send();
}
</script>
</head>
<body>
<form>
<h2>Enter a technology name : </h2>
<input type = "text" size = "36" onkeyup = "showResult(this.value)">
<div id = "ajax-autocomplete-main"></div>
</form>
</body>
</html>
Then...
<?php
$xmlDoc = new DOMDocument();
$xmlDoc->load( "ajax-autocomplete.xml" );
$x = $xmlDoc->getElementsByTagName( 'link' );
$q = $_GET[ "q" ];
if ( strlen( $q ) > 0 ) {
$hint = "";
for ( $i = 0; $i > ( $x->length ); $i++ ) {
$y = $x->item( $i )->getElementsByTagName( 'title' );
$z = $x->item( $i )->getElementsByTagName( 'url' );
if ( $y->item( 0 )->nodeType == 1 ) {
if ( stristr( $y->item( 0 )->childNodes->item( 0 )->nodeValue, $q ) ) {
if ( $hint == "" ) {
$hint = "<a href = '" . $z->item( 0 )->childNodes->item( 0 )->nodeValue . "' target='_blank'>" .
$y->item( 0 )->childNodes->item( 0 )->nodeValue . "</a>";
} else {
$hint = $hint . "<br/><a href = '" .
$z->item( 0 )->childNodes->item( 0 )->nodeValue . "' target='_blank'>" .
$y->item( 0 )->childNodes->item( 0 )->nodeValue . "</a>";
}
}
}
}
}
if ( $hint == "" ) {
$response = "Please enter a valid technology name...";
} else {
$response = $hint;
}
echo $response;
?>
Now the XML file.
<pages>
<link>
<title>PHP</title>
<url>https://reflex001.com/en/resources/php-mysql</url>
</link>
<link>
<title>JavaScript</title>
<url>https://reflex001.com/en/resources/javascript</url>
</link>
</pages>
AJAX Poll
AJAX Poll is used to quickly print clear results.
<html>
<head>
<script>
function getPoll(int) {
var xmlhttp=new XMLHttpRequest();
xmlhttp.onreadystatechange=function() {
if (this.readyState==4 && this.status==200) {
document.getElementById("MainPoll").innerHTML=this.responseText;
}
}
xmlhttp.open("GET","main-poll.php?vote="+int,true);
xmlhttp.send();
}
</script>
</head>
<body>
<div id="MainPoll">
<h3>Are you ready to become a great programmer ?</h3>
<form>
Yes: <input type="radio" name="vote" value="0" onclick="getPoll(this.value)"><br>
No: <input type="radio" name="vote" value="1" onclick="getPoll(this.value)">
</form>
</div>
</body>
</html>
Then (main-poll.php)...
<?php
$vote = $_REQUEST['vote'];
$filename = "result.txt";
$content = file($filename);
$array = explode("||", $content[0]);
$yes = $array[0];
$no = $array[1];
if ($vote == 0) {
$yes = $yes + 1;
}
if ($vote == 1) {
$no = $no + 1;
}
$insertvote = $yes."||".$no;
$fp = fopen($filename,"w");
fputs($fp,$insertvote);
fclose($fp);
?>
<h1>This is the result:</h1>
<table>
<tr>
<td>Yes:</td>
<td><img src="cross.gif"
width='<?php echo(100*round($yes/($no+$yes),2)); ?>'
height='16'>
<?php echo(100*round($yes/($no+$yes),2)); ?>%
</td>
</tr>
<tr>
<td>No:</td>
<td><img src="cross.gif"
width='<?php echo(80*round($no/($no+$yes),2)); ?>'
height='16'>
<?php echo(80*round($no/($no+$yes),2)); ?>%
</td>
</tr>
</table>
Now the result.txt file (result example). Don't forget to create the GIF image...
1||0
AJAX Database
AJAX can also be used in database management. See example below ( you need to create a database first, then those two files) :
<html>
<head>
<script>
function showCategory(str) {
if (str == "") {
document.getElementById("txtHint").innerHTML = "";
return;
} else {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
document.getElementById("txtHint").innerHTML = this.responseText;
}
};
xmlhttp.open("GET","ajax-database-main.php?q="+str,true);
xmlhttp.send();
}
}
</script>
</head>
<body>
<form>
<select name="Categories" onchange="showCategory(this.value)">
<option value="">Select a subject category :</option>
<option value="1">Ecology</option>
<option value="2">Global News</option>
<option value="3">History</option>
<option value="4">Technology</option>
</select>
</form>
<br>
<div id="txtHint"><b>Result...</b></div>
</body>
</html>
Then :
<!DOCTYPE html>
<html>
<head>
<style>
table {
width: 100%;
border-collapse: collapse;
}
table, td, th {
border: 2px solid black;
padding: 10px;
}
th {
text-align: left;
}
</style>
</head>
<body>
<?php
$q = intval( $_GET[ 'q' ] );
$con = mysqli_connect( 'localhost', 'USER', 'PASSWORD' );
if ( !$con ) {
die( 'Could not connect to : ' . mysqli_error( $con ) );
}
mysqli_select_db( $con, "DATABASE" );
$sql = "SELECT * FROM Category WHERE Category_id = '" . $q . "'";
$result = mysqli_query( $con, $sql );
echo "<table>
<tr>
<th>ID</th>
<th>Subject</th>
<th>Popularity</th>
<th>Year</th>
<th>Articles</th>
<th>Comments</th>
</tr>";
while ( $row = mysqli_fetch_array( $result ) ) {
echo "<tr>";
echo "<td>" . $row[ 'Category_id' ] . "</td>";
echo "<td>" . $row[ 'Category_Subject' ] . "</td>";
echo "<td>" . $row[ 'Category_Popularity' ] . "</td>";
echo "<td>" . $row[ 'Category_Year' ] . "</td>";
echo "<td>" . $row[ 'Category_Articles' ] . "</td>";
echo "<td>" . $row[ 'Category_Comments' ] . "</td>";
echo "</tr>";
}
echo "</table>";
mysqli_close( $con );
?>
</body>
</html>
AJAX XML Parser and RSS Feed
It is possible to use an XML file with AJAX :
<html>
<head>
<script>
function showMovies(str) {
if (str=="") {
document.getElementById("txtHint").innerHTML="";
return;
}
var xmlhttp=new XMLHttpRequest();
xmlhttp.onreadystatechange=function() {
if (this.readyState==4 && this.status==200) {
document.getElementById("txtHint").innerHTML=this.responseText;
}
}
xmlhttp.open("GET","main-movies.php?q="+str,true);
xmlhttp.send();
}
</script>
</head>
<body>
<form>
Choose a movie in this menu :
<select name="movies" onchange="showMovies(this.value)">
<option value="">Choose a movie:</option>
<option value="E.T.">E.T.</option>
<option value="Indiana Jones">Indiana Jones</option>
<option value="Star Wars">Star Wars</option>
</select>
</form>
<div id="txtHint"><b>All the weekly movies are presented in this menu.</b></div>
</body>
</html>
Then :
<?php
$q=$_GET["q"];
$xmlDoc = new DOMDocument();
$xmlDoc->load("movies.xml");
$x=$xmlDoc->getElementsByTagName('TITLE');
for ($i=0; $i<=$x->length-1; $i++) {
if ($x->item($i)->nodeType==1) {
if ($x->item($i)->childNodes->item(0)->nodeValue == $q) {
$y=($x->item($i)->parentNode);
}
}
}
$movies=($y->childNodes);
for ($i=0;$i<$cd->length;$i++) {
if ($movies->item($i)->nodeType==1) {
echo("<b>" . $movies->item($i)->nodeName . ":</b> ");
echo($movies->item($i)->childNodes->item(0)->nodeValue);
echo("<br>");
}
}
?>Now the XML file.
<MOVIELIST>
<MOVIE>
<TITLE>E.T.</TITLE>
<DIRECTOR>Steven Spielberg</DIRECTOR>
<YEAR>1982</YEAR>
</MOVIE>
<MOVIE>
<TITLE>Indiana Jones</TITLE>
<DIRECTOR>George Lucas/Steven Spielberg</DIRECTOR>
<YEAR>1981</YEAR>
</MOVIE>
<MOVIE>
<TITLE>Star Wars</TITLE>
<DIRECTOR>George Lucas<DIRECTOR>
<YEAR>1977</YEAR>
</MOVIE>
</MOVIELIST>
Arrays
As in most languages, the array is one of the fundamental elements of programming field. There are three types with PHP language :
- Numeric. The most basic one...
Example 1 :
<html>
<body>
<?php
$numbers = array( 1, 2, 3, 4, 5 );
foreach ( $numbers as $value ) {
echo "The value is $value <br />";
}
?>
</body>
</html>
Example 2 :
<html>
<body>
<?php
$numbers[ 0 ] = "Canada";
$numbers[ 1 ] = "France";
$numbers[ 2 ] = "Italy";
$numbers[ 3 ] = "USA";
foreach ( $numbers as $value ) {
echo "The value is $value <br />";
}
?>
</body>
</html>
- Associative. The index consists of strings.
Example 1 :
<html>
<body>
<?php
$velocity = array( "Car1" => 12000, "Car2" => 10000, "Car3" => 6000 );
echo "Car 1 price is " . $velocity[ 'Car1' ] . "<br />";
echo "Car 2 price is " . $velocity[ 'Car2' ] . "<br />";
echo "Car 3 price is " . $velocity[ 'Car3' ] . "<br />";
?>
</body>
</html>
Example 2 :
<html>
<body>
<?php
$velocity[ 'Car1' ] = "powerful";
$velocity[ 'Car2' ] = "interesting";
$velocity[ 'Car3' ] = "bad";
echo "Car1 velocity is " . $velocity[ 'Car1' ] . "<br />";
echo "Car2 velocity is " . $velocity[ 'Car2' ] . "<br />";
echo "Car3 velocity is " . $velocity[ 'Car3' ] . "<br />";
?>
</body>
</html>
- Multidimensional. An array which contains several other arrays and values...
Example 1 :
<html>
<body>
<?php
$evaluation = array(
"Car1" => array(
"Velocity" => 80,
"Design" => 90,
"Eco-responsibility" => 40
),
"Car2" => array(
"Velocity" => 70,
"Design" => 60,
"Eco-responsibility" => 60
),
"Car3" => array(
"Velocity" => 50,
"Design" => 40,
"Eco-responsibility" => 30
),
"Car4" => array(
"Velocity" => 30,
"Design" => 30,
"Eco-responsibility" => 20
)
);
echo "Evaluation velocity (on 100%) for Car 1 is : ";
echo $evaluation[ 'Car1' ][ 'Velocity' ] . "<br />";
echo "Evaluation design (on 100%) for Car 2 is : ";
echo $evaluation[ 'Car2' ][ 'Design' ] . "<br />";
echo "Evaluation eco-responsibility (on 100%) for Car 3 is : ";
echo $evaluation[ 'Car3' ][ 'Eco-responsibility' ] . "<br />";
echo "Evaluation eco-responsibility (on 100%) for Car 4 is : ";
echo $evaluation[ 'Car4' ][ 'Eco-responsibility' ] . "<br />";
?>
</body>
</html>
Basic Syntax
Bugs
Classes/Objects
Debugging
Built-In Functions
Calendar
Callback Functions
Comments
Coding Standard
Compiler
Constants
Constructor
Cookies
Cookies are basic text files that are stored on the user computer and kept there for tracking (HTTP header).
Example (PHP) :
GET / HTTP/1.0
Connection: Keep-Alive
User-Agent: Mozilla/4.6 (X11; I; Linux 2.2.6-15apmac ppc)
Host: zink.demon.co.fr:2820
Accept: image/gif, */*
Accept-Encoding: gzip
Accept-Language: fr
Accept-Charset: iso-8859-1,*,utf-8
Cookie: name=xyz
Setting cookies script example :
setcookie(name, value, expire, path, domain, security);
Cookies access script example :
<html>
<head>
<title>Cookies Access</title>
</head>
<body>
<?php
echo $_COOKIE["name"]. "<br />";
echo $HTTP_COOKIE_VARS["name"]. "<br />";
echo $_COOKIE["age"] . "<br />";
echo $HTTP_COOKIE_VARS["age"] . "<br />";
?>
</body>
</html>
isset() function example :
<html>
<head> <title>isset() function example</title>
</head>
<body>
<?php
if( isset($_COOKIE["name"]))
echo "Welcome " . $_COOKIE["name"] . "<br />";
else
echo "Sorry... Not recognized" . "<br />";
?>
</body>
</html>
Cookie deletion script example :
<?php
setcookie( "name", "", time()- 60, "/","", 0);
setcookie( "age", "", time()- 60, "/","", 0);
?>
<html>
<head>
<title>Cookie Deletion</title>
</head>
<body>
<?php echo "Deleted Cookies" ?>
</body>
</html>
Data Types
Date & Time
Decision Making
Echo / Print
Destructor
Design Patterns
Error Handling
DOM Parser
Exceptions
File Create/Write
File Inclusion
File Handling
File Upload
Filesystem
File Open/Read
Filters
Form Handling
Form Introduction
Files & I/O
Form Required
Form URL/E-mail
Form Validation
Frameworks
Functions
Get & Post
If...Else...Elseif
Include
Interfaces
Inheritance
JSON
Iterables
Libxml
Keywords
Login
Loop Types
There is 4 loop types :
- for
- foreach
- while
- do...while
Mail
Math
MySQL Connect
Misc
MySQL Create DB
MySQL Create Table
MySQL Database
MySQL Delete Data
MySQL Get Last ID
MySQL Insert Data
MySQL Login
MySQL Limit Data
MySQL Insert Multiple
MySQL Prepared
MySQL Order By
MySQL Select Data
MySQL Update Data
MySQL Where
Namespaces
Numbers
Output Control
Operators
MySQLi
Paypal Integration
Predefined Variables
RegEx
SAX Parser
Sending Emails Sessions
Static Properties
SimpleXM
Static Methods
Stream
Switch
Superglobals
Timezones
Variable Handling
Variable Types
Traits
String
XML Expat
XML Parser
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