Php: Difference between revisions

Revision as of 21:50, 21 April 2013

Server side programming language

frameworks

php.net

LAMP

error logs /cat /var/log/apache2/error.log / run file

Hello World

Every block of PHP code must start with <?php and end with ?>.
You need to place a semi-colon (;) at the end of each line of PHP code.
variable names must start with a dollar sign ($).

<!DOCTYPE html>
<meta charset=utf-8>
<title>PHP Test</title>
<?php
 echo 'Hello World';
?>

Mixing with HTML

<?php 
 // this is a PHP comment
$myHeader = "Header made with echo";
echo "<h3>".$myHeader."</h3>";
?>

<!--  Is similar to (note HTML comment)  -->
<?php $myHeader2 = "Header made with with HTML"; ?>
<h3> <?php echo $myHeader2; ?> </h3>

Syntax

function myFunction() { //declares a function, this is named myFunction
 return 'John Doe'; //returns the value 'John Doe'
}

echo 'My name is ' . myFunction() . '!'; //outputs the text concatenated with the return value of myFunction.
 //myFunction is called as a result of this syntax.
//The result of the output will be 'My name is John Doe!'

Weirdness of PHP

<?php
if("foo" == TRUE){
	echo 'YES! foo == TRUE, but we didnt define it yet? Well okay....</br></br>';
}

if("foo" == 0){
	echo 'Huh? "foo" is also a number?</br></br>';
}

if(TRUE == 0){
	echo 'therefor True is also 0, right?! ';
}else{
	echo "WRONG!";
}

?>

@@ Line 14: / Line 14: @@
 ====Hello World====
-*Every block of PHP code must start with <?php and end with ?>.
+* Every block of PHP code must start with <?php and end with ?>.
-*You need to place a semi-colon (;) at the end of each line of PHP code.
+* You need to place a semi-colon (;) at the end of each line of PHP code.
+* variable names must start with a dollar sign ($).
 <source lang="php">