Getting started with PHP

Your PHP code goes inside the

<?php  
code here  
?>

To display text in HTML output page

echo "this is output";  

Make sure to end your line of PHP code with a semicolon

;

String Manipulations

<?php  
$name = "Luke Perry";
echo strlen($name); // 10  
echo substr($name, 0, 3); // Luk  
echo strtoupper($name); // LUKE PERRY  
echo strpos($name, "e Perry"); // 3  
// concatenation
echo "hello" . "user";  
?>

Variables

All variable names in PHP start with a dollar sign

$temp

Comment

comment is started with either of following code

//

or

#

Operators

> Greater than
< Less than  
<= Less than or equal to  
>= Greater than or equal to
== Equal to
!= Not equal to

Conditional Sentence

    if ( 2 > 10) {
        echo " ok";
        }
    else if ( 2 == 33 ) {
        echo "ccc";
        }
    else if ( 3 == 34) {
        echo "this is 3";
    }
    else {
        echo "nothing mathcn";
        }

switch

    switch (2) {
        case 0:
            echo 'The value is 0';
            break;
        case 1:
            echo 'The value is 1';
            break;
        case 2:
            echo 'The value is 2';
            break;
        default:
            echo "The value isn't 0, 1 or 2";
    }

Using or clause with switch

    switch ($i) {
        case 0:
            echo '$i is 0.';
            break;
        case 1:
        case 2:
        case 3:
        case 4:
        case 5:
            echo '$i is somewhere between 1 and 5.';
            break;
        case 6:
        case 7:
            echo '$i is either 6 or 7.';
            break;
        default:
            echo "I don't know how much $i is.";
    }

Working with Array

defining array and adding new element

      <?php
        // Add your array elements after
        // "Beans" and before the final ")"
        $array = array("Egg", "Tomato", "Beans" );        
      ?>

<?php  
$states = array();
$array = array_push($states, "Montana");
$array = array_push($states, "North Carolina");
$array = array_push($states, "California");
echo $array; // returns 3  
var_dump($states);  
?>

Pushing multiple elements together

<?php  
$states = array(); // target array
$array = array_push($states, 
"Montana", 
"North Carolina", 
"California");
echo $array; // returns 3  
var_dump($games);  
?>

Print array

<?php  
echo $tens[2];  
echo $tens{2};  
?>

Modify and delete array element

$languages[1] = "green";
unset($array[2]);  
unset($array);  

Loop

        foreach($languages as $lang) {
          print "<p>$lang</p>";
        }

another example

      <?php
        // Echoes the first five even numbers
        for ($i = 2; $i < 11; $i = $i + 2) {
          echo $i;
        }
      ?>