$name

    $Age

    $_debugging

    $MAXIMUM_IMPACT

    $what = "Fred";

    $what = 35;

    $what = array('Fred', '35', 'Wilma');

    $day = 60 * 60 * 24;

    echo "There are $day seconds in a day.\n";

    There are 86400 seconds in a day.

    if ($uninitialized_variable === NULL) {

      echo "Yes!";

    }

    Yes!

    $foo = 'bar';

    $$foo = 'baz';

    $black =& $white;

    $big_long_variable_name = "PHP";

    $short =& $big_long_variable_name;

    $big_long_variable_name .= " rocks!";

    print "\$short is $short\n";

    print "Long is $big_long_variable_name\n";

    $short is PHP rocks!

    Long is PHP rocks!

    $short = "Programming $short";

    print "\$short is $short\n";

    print "Long is $big_long_variable_name\n";

    $short is Programming PHP rocks!

    Long is Programming PHP rocks!

    <? include 'header.html'; ?>

    content

    <? include 'footer.html'; ?>

    require 'codelib.inc';

    mysub(  );               // defined in codelib.inc

    <? require 'design.inc';

       header(  );

    ?>

    content

    <? footer(  ); ?>

    include 'http://www.example.com/codelib.inc';

    $some_value = function_name( [ parameter, ... ] );

    // strlen(  ) is a built-in function that returns the length of a string

    $length = strlen("PHP"); // $length is now 3



    // sin(  ) and asin(  ) are the sine and arcsine math functions

    $result = sin(asin(1)); // $result is the sine of arcsin(1), or 1.0



    // unlink(  ) deletes a file

    $result = unlink("functions.txt"); // false if unsuccessful

    function [&] function_name ( [ parameter [, ... ] ] )

    {

      statement list

    }

    <? function column(  ) { ?>

    </td><td>

    <? } ?>

function strcat($left, $right) {

 $combined_string = $left . $right;

 return $combined_string;

}

    $a = 3;



    function foo(  ) {

      $a += 2;

    }



    foo(  );

    echo $a;

    global var1, var2, ...

    $a = 3;



    function foo(  ) {

      global $a;

      $a += 2;

    }



    foo(  );

    echo $a;

    function return_one(  ) {

       return 42;

    }

    function return_two (  ) {

       return array("Fred", 35);

    }

    $names = array("Fred", "Barney", "Wilma", "Betty");

    function & find_one($n) {

       global $names;

       return $names[$n];

    }

    $person =& find_one(1);           // Barney

    $person = "Barnetta";             // changes $names[1]

    switch($which) {

      case 'first':

        first(  );

        break;



      case 'second':

        second(  );

        break;



      case 'third':

        third(  );

        break;

    }

    $which(  );  // if $which is "first," the function first(  ) is called, etc...

    $yes_or_no = function_exists(function_name);

    if(function_exists($which)) {

      $which(  );  // if $which is "first," the function first(  ) is called, etc...

    }

    $f = 'echo';

    $f('hello, world');  // does not work

    $func_name = create_function(args_string, code_string);

$lambda = create_function('$a,$b', 'return(strlen($a) - strlen($b));');

$array = array('really long string here, boy', 'this', 'middling length', 'larger');

usort($array, $lambda);

print_r($array);

    $string = 'Hello, world';

    $length = strlen($string);             // $length is 12

    $string = 'Hello';

    for ($i=0; $i < strlen($string); $i++) {

      printf("The %dth character is %s\n", $i, $string{$i});

    }

    The 0th character is H

    The 1th character is e

    The 2th character is l

    The 3th character is l

    The 4th character is o

    $age['Fred']

    $shows[2]

    define('index',5);

    echo $array[index];               // retrieves $array[5], not $array['index'];

    $age["Clone$number"]

    // these are wrong

    print "Hello, $person['name']";

    print "Hello, $person["name"]";

    // this is right

    print "Hello, $person[name]";

    // $addresses not defined before this point

    echo $addresses[0];                    // prints nothing

    echo $addresses;                       // prints nothing

    $addresses[0] = 'spam@cyberpromo.net';

    echo $addresses;                       // prints "Array"

    $addresses[0] = 'spam@cyberpromo.net';

    $addresses[1] = 'abuse@example.com';

    $addresses[2] = 'root@example.com';

    // ...

    $price['Gasket'] = 15.29;

    $price['Wheel']  = 75.25;

    $price['Tire']   = 50.00;

    // ...

    $addresses = array('spam@cyberpromo.net', 'abuse@example.com',

                       'root@example.com');

    $price = array('Gasket' => 15.29,

                   'Wheel'  => 75.25,

                   'Tire'   => 50.00);

    $price = array('Gasket'=>15.29,'Wheel'=>75.25,'Tire'=>50.00);

    $addresses = array(  );

    $days = array(1 => 'Monday',   'Tuesday', 'Wednesday',

                       'Thursday', 'Friday',  'Saturday', 'Sunday');

    // 2 is Tuesday, 3 is Wednesday, etc.

    $row_0 = array(1, 2, 3);

    $row_1 = array(4, 5, 6);

    $row_2 = array(7, 8, 9);

    $multi = array($row_0, $row_1, $row_2);

    $value = $multi[2][0];                 // row 2, column 0. $value = 7

    echo("The value at row 2, column 0 is {$multi[2][0]}\n");

    The value at row 2, column 0 is Array[0]

    list($variable, ...) = $array;

    $person = array('Fred',  35, 'Betty');

    list($name, $age, $wife) = $person;    // $name is 'Fred', $age is 35, $wife is

    'Betty'

    $person = array('Fred', 35, 'Betty');

    list($name, $age) = $person;         // $name is 'Fred', $age is 35

    $values = array('hello', 'world');

    list($a, $b, $c) = $values;            // $a is 'hello', $b is 'world', $c is NULL

    $values = range('a', 'e');             // use range to populate the array

    list($m,,$n,,$o) = $values;            // $m is 'a', $n is 'c', $o is 'e'

    $subset = array_slice(array, offset, length);

    $people = array('Tom', 'Dick', 'Harriet', 'Brenda', 'Jo');

    $middle = array_slice($people, 2, 2); // $middle is array('Harriet', 'Brenda')

    $person = array('name' => 'Fred', 'age' => 35, 'wife' => 'Betty');

    $name = 'Fred';

    $age  = 35;

    $wife = 'Betty';

    extract($person);                // $name, $age, and $wife are now set

    $shape = "round";

    $array = array("cover" => "bird", "shape" => "rectangular");

    extract($array, EXTR_PREFIX_ALL, "book");

    echo "Cover: $book_cover, Book Shape: $book_shape, Shape: $shape";

    Cover: bird, Book Shape: rectangular, Shape: round

    $object = new Class;

    $rasmus = new Person;

    $rasmus = new 'Person';                 // does not work

    $object = new Person('Fred', 35);

    $class = 'Person';

    $object = new $class;

    // is equivalent to

    $object = new Person;

    $account = new Account;

    $object = 'account'

    ${$object}->init(50000, 1.10);  // same as $account->init

    $object->propertyname

    $object->methodname([arg, ... ])

    printf("Rasmus is %d years old.\n", $rasmus->age);  // property access

    $rasmus->birthday(  );                                   // method call

    $rasmus->set_age(21);                               // method call with arguments

    $clan = $rasmus->family('extended');

    $prop = 'age';

    echo $rasmus->$prop;

    HTML::p("Hello, world");

    $f = new Person('Fred', 35);

    $b = $f;                               // $b and $f point at same object

    $b->set_name('Barney');

    printf("%s and %s are best friends.\n", $b->get_name(  ), $f->get_name(  ));

    // outputs: Barney and Barney are best friends.

    $f = new Person('Fred', 35);

    $b = clone $f;                         // make a copy

    $b->set_name('Barney');                // change the copy

    printf("%s and %s are best friends.\n", $b->get_name(  ), $f->get_name(  ));

    // outputs: Fred and Barney are best friends.

    class classname [ extends baseclass ]

    {

        [ var $property [ = value ]; ... ]



        [ function functionname (args) {

              // code

          }

          ...

        ]

    }

    class Person {

        var $name;



        function get_name (  ) {

            return $this->name;

        }



        function set_name ($new_name) {

            $this->name = $new_name;

        }

    }

    $encoded = serialize(something);

    $something = unserialize(encoded);

    <?php

     include('object_definitions.inc');  // load object definitions

     session_start(  );                    // load persistent variables

    ?>

    <html>...

    GET /index.html HTTP/1.1

    User-Agent: Mozilla/5.0 (Windows 2000; U) Opera 6.0  [en]

    Accept: image/gif, image/jpeg, text/*, */*

    HTTP/1.1 200 OK

    <?php

     header('Content-Type: text/plain');

    ?>

    Date: today

    From: fred

    To: barney

    Subject: hands off!



    My lunchbox is mine and mine alone. Get your own,

    you filthy scrounger!

    Warning:  Cannot add header information - headers already sent

    <?php

     header('Location: http://www.example.com/elsewhere.html');

     exit(  );

    ?>

    http://www.example.com/catalog.php?userid=123

    if ($_SERVER['HTTPS'] !== 'on') {

      die("Must be a secure connection.");

    }

INSERT INTO books VALUES (4, 'I, Robot', '0-553-29438-5', 1950)

INSERT INTO books (authorid, title, ISBN, pub_year) VALUES (4, 'I, Robot, 

'0-553-29438-5', 1950)

<html>

  <head>

    <title>Example Page</title>

  </head>

  <body>

    This page contains two images.

    <img src="image1.jpg" alt="Image 1">

    <img src="image2.jpg" alt="Image 2">

  </body>

</html>

GET /page.html HTTP/1.0

GET /image1.jpg HTTP/1.0

GET /image2.jpg HTTP/1.0

Content-Type: text/html

Content-Type: image/jpeg

Content-Type: image/jpeg

<html>

  <head>

    <title>Example Page</title>

  </head>

  <body>

    This page contains two images.

    <img src="image1.php" alt="Image 1">

    <img src="image2.php" alt="Image 2">

  </body>

</html>

gd



GD Support        enabled

GD Version        2.0 or higher

FreeType Support  enabled

FreeType Linkage  with freetype

JPG Support       enabled

PNG Support       enabled

WBMP Support      enabled

<?php

 $im = ImageCreate(200,200);

 $white = ImageColorAllocate($im,0xFF,0xFF,0xFF);

 $black = ImageColorAllocate($im,0x00,0x00,0x00);

 ImageFilledRectangle($im,50,50,150,150,$black);

 header('Content-Type: image/png');

 ImagePNG($im);

?>

Figure 9-1: A black square on a white background

<img src="black.php">

$image = ImageCreate(width, height);

$color = ImageColorAllocate(image, red, green, blue);

<?php

 $im = ImageCreate(200,200);

 $white = ImageColorAllocate($im,0xFF,0xFF,0xFF);

 $black = ImageColorAllocate($im,0x00,0x00,0x00);

 ImageFilledRectangle($im,50,50,150,150,$black);

 ImageString($im,5,50,160,"A Black Box",$black);

 Header('Content-Type: image/png');

 ImagePNG($im);

?>

Figure 9-3: The black box image with added text

ImageString(image, font, x, y, text, color);

Fonts in GD are identified by numbers. The five built-in fonts are shown in Figure 9-4.

Figure 9-4: Native GD fonts

The code used to show you these fonts follows:

<?php

$im = ImageCreate(200,200);

$black = ImageColorAllocate($im,0x00,0x00,0x00);



ImageString($im,1,10,10,"Font 1: ABCDEfghij",$black);

ImageString($im,2,10,30,"Font 2: ABCDEfghij",$black);

ImageString($im,3,10,50,"Font 3: ABCDEfghij",$black);

ImageString($im,4,10,70,"Font 4: ABCDEfghij",$black);

ImageString($im,5,10,90,"Font 5: ABCDEfghij",$black);



Header('Content-Type: image/png');

ImagePNG($im);

?>

You can create your own fonts and load them into GD using the ImageLoadFont( ) function. However, these fonts are binary and architecture-dependent. Using TrueType fonts with the TrueType functions in GD provides much more flexibility.

<?php

 $font = 'times';

 if (!$size) $size = 12;

 $im = ImageCreateFromPNG('button.png');

 // calculate position of text

 $tsize = ImageTTFBBox($size,0,$font,$text);

 $dx = abs($tsize[2]-$tsize[0]);

 $dy = abs($tsize[5]-$tsize[3]);

 $x = ( ImageSx($im) - $dx ) / 2;

 $y = ( ImageSy($im) - $dy ) / 2 + $dy;

 // draw text

 $black = ImageColorAllocate($im,0,0,0);

 ImageTTFText($im, $size, 0, $x, $y, $black, $font, $text);

 header('Content-Type: image/png');

 ImagePNG($im);

?>

Figure 9-7: Blank Button

<img src="button.php?text=PHP+Button">

Figure 9-8: Button with generated text label

<img src="button.php?text=<?php echo urlencode('PHP Button')?>">

ImageCopyResized(dest, src, dx, dy, sx, sy, dw, dh, sw, sh);

ImageCopyResampled(dest, src, dx, dy, sx, sy, dw, dh, sw, sh);

<?php

 $src = ImageCreateFromJPEG('php.jpg');

 $width = ImageSx($src);

 $height = ImageSy($src);

 $x = $width/2; $y = $height/2;

 $dst = ImageCreateTrueColor($x,$y);

 ImageCopyResampled($dst,$src,0,0,0,0,$x,$y,$width,$height);

 header('Content-Type: image/png');

 ImagePNG($dst);

?>

Figure 9-9: Original php.jpg image

Figure 9-10: Resulting 1/4-sized image

$image = ImageCreateTrueColor(width, height);

$color = ImageColorResolveAlpha(image, red, green, blue, alpha);

  High Byte                  Low Byte

{Alpha Channel} {Red} {Green} {Blue}

<book isbn="1-56592-610-2">

  <title>Programming PHP</title>

  <authors>

    <author>Rasmus Lerdorf</author>

    <author>Kevin Tatroe</author>

    <author>Peter MacIntyre</author>

  </authors>

</book>

<br>

<br />

<book><title>Programming PHP</title></book>

<book><title>Programming PHP</book></title>

<?xml version="1.0" ?>

<?xml version="1.0" ?>

<library>

  <title>Programming PHP</title>

  <title>Programming Perl</title>

  <title>Programming C#</title>

</library>

<?xml version="1.0" ?>

<title>Programming PHP</title>

<title>Programming Perl</title>

<title>Programming C#</title>

<?php

 echo '<?xml version="1.0" encoding="ISO-8859-1" ?>';

?>

<?php header('Content-Type: text/xml'); ?>

<?xml version='1.0' encoding='ISO-8859-1' ?>

<!DOCTYPE rss PUBLIC '-//Netscape Communications//DTD RSS 0.91//EN'

 'http://my.netscape.com/publish/formats/rss-0.91.dtd'>

<rss version="0.91">

  <channel>

    <?php

     // news items to produce RSS for

     $items = array(

                    array('title' => 'Man Bites Dog',

                          'link'  => 'http://www.example.com/dog.php',

                          'desc'  => 'Ironic turnaround!'),

                    array('title' => 'Medical Breakthrough!',

                          'link'  => 'http://www.example.com/doc.php',

                          'desc'  => 'Doctors announced a cure for me.')

                    );



     foreach($items as $item) {

       echo "<item>\n";

       echo "  <title>{$item[title]}</title>\n";

       echo "  <link>{$item[link]}</link>\n";

       echo "  <description>{$item[desc]}</description>\n";

       echo "  <language>en-us</language>\n";

       echo "</item>\n";

     }

    ?>

  </channel>

</rss>

$parser = new DomDocument(  );

$rootNode = $parser->load('BookList.xml');



processNodes($rootNode);



function processNodes($node) {

  $children = $node->children;



  foreach ($children as $child) {

    if ($child->nodeType == XML_TEXT_NODE) {

      echo $child->noteValue;

    }

    else if ($child->nodeType == XML_ELEMENT_NODE) {

      processNodes($child);

    }

  }

}

$document= simplexml_load_file('bookparse.xml');

foreach ($document->library->book as $book) {

  echo $book->title;

}

$document= simplexml_load_file('bookparse.xml');

foreach ($document->library->children(  ) as $node) {

  foreach ($node->attributes(  ) as $attribute) {

    echo "$attribute\n";

  }

}

$document= simplexml_load_file('bookparse.xml');

foreach ($document->library->book as $book) {

  $book->title = 'New Title';

}



file_put_contents('bookparse.xml', $document->asXML(  ));

$xslt = new XSLTProcessor;

$xml = new DOMDocument

$xml->load($xml_file);



$xsl = new DOMDocument;

$xsl->load($xsl_file);

$xslt->importStyleSheet($xsl);

$result = $xslt->transformToXML($xml);

<?xml version="1.0" ?>



<news xmlns:news="http://slashdot.org/backslash.dtd">

  <story>

    <title>O'Reilly Publishes Programming PHP</title>

    <url>http://example.org/article.php?id=20020430/458566</url>

    <time>2002-04-30 09:04:23</time>

    <author>Rasmus and some others</author>

  </story>



  <story>

    <title>Transforming XML with PHP Simplified</title>

    <url>http://example.org/article.php?id=20020430/458566</url>

    <time>2002-04-30 09:04:23</time>

    <author>k.tatroe</author>

  </story>

</news>

<form action="process.php" method="POST">

Please select a color:

<select name="color">

  <option value="red">red</option>

  <option value="green">green</option>

  <option value="blue">blue</option>

</select>

<input type="submit" />

</form>

<?php



$html = array(  );



$html['username'] = htmlentities($clean['username'],

  ENT_QUOTES, 'UTF-8');



echo "<p>Welcome back, {$html['username']}.</p>";



?>

<a href="http://host/script.php?var=value">Click Here</a>

<?php



$html = array(  );

$url = array(  );



$url['value'] = urlencode($value);



$link = "http://host/script.php?var={$url['value']}";

$html['link'] = htmlentities($link, ENT_QUOTES, 'UTF-8');



?>



<a href="<?php echo $html['link']; ?>">Click Here</a>

<?php



echo $_POST['username'];



?>

<?php



$html = array(  );



$html['username'] = htmlentities($_POST['username'],

  ENT_QUOTES, 'UTF-8');



echo $html['username'];



?>

<a href="http://host/login.php?PHPSESSID=1234">Log In</a>

<?php



if (check_auth($_POST['username'], $_POST['password']))

{

    $_SESSION['auth'] = TRUE;

    session_regenerate_id(  );

}



?>

<html>

  <head>

    <title>Here are the keys...</title>

  </head>

  <body>

    <?php if ($code) {

      echo "Executing code...";



      eval(stripslashes($code));           // BAD!

    } ?>



  <form>

      <input type="text" name="code" />

      <input type="submit" name="Execute Code" />

  </form>

  </body>

</html>

include('/etc/passwd');

disable_functions = system

eval("2 + $user_input");

system("ls $directory");

ls /tmp;cat /etc/passwd

$cleaned_up = escapeshellarg($directory);

system("ls $cleaned_up");

ls '/tmp;cat /etc/passwd'

    <html>

      <head>

        <title>User Information</title>

      </head>



      <body>

        <?php if (!empty($_GET['name'])) {

          // do something with the supplied values

        ?>



        <p><font face="helvetica,arial">Thank you for filling out the form,

            <?php echo $_GET['name'] ?>.</font></p>

    <?php }

    else { ?>

          <p><font face="helvetica,arial">Please enter the

          following information:</font></p>



          <form action="<?php echo $_SERVER['PHP_SELF'] ?>">

            <table>

              <tr>

                <td>Name:</td>

                <td><input type="text" name="name" /></td>

              </tr>

            </table>

          </form>

        <?php } ?>

      </body>

    </html>

    emalloc( )

    efree( )

    estrdup( )

    estrndup( )

    ecalloc( )

    erealloc( )

    foo.c(123) :  Freeing 0x0821E5FC (20 bytes), script=foo.php

    Last leak repeated 1 time

    ---------------------------------------

    foo.c(124) : Block 0x08219C94 status:

    Beginning:      Overrun (magic=0x00000000, expected=0x7312F8DC)

          End:      Unknown

    ---------------------------------------

    foo.c(124) : Block 0x0821EB1C status:

    Beginning:      Overrun (magic=0x00000000, expected=0x7312F8DC)

          End:      Unknown

    ---------------------------------------

    123:   s = emalloc(6);

    124:   strcpy(s,"Rasmus");

    125:   efree(s);

    ---------------------------------------

    foo.c(125) : Block 0x08219CB8 status:

    Beginning:      OK (allocated on foo.c:123, 6 bytes)

          End:      Overflown (magic=0x2A8FCC00 instead of 0x2A8FCC84)

                    1 byte(s) overflown

    ---------------------------------------

    foo.c(125) : Block 0x08219C40 status:

    Beginning:      OK (allocated on foo.c:123, 6 bytes)

          End:      Overflown (magic=0x2A8FCC00 instead of 0x2A8FCC84)

                    1 byte(s) overflown

    ---------------------------------------

    typedef union _zvalue_value {

            long lval;

            double dval;

            struct {

                    char *val;

                    int len;

            } str;

            HashTable *ht;

            zend_object_value obj;

    } zvalue_value;

    struct _zval_struct {

            zvalue_value value;

            zend_uint refcount;

            zend_uchar type;

            zend_uchar is_ref;

    };

    int zend_parse_parameters(int num_args TSRMLS_DC, char *type_spec, ...);

    int zend_parse_parameters_ex(int flags, int num_args TSRMLS_DC,

      char *type_spec, ...);

    char *arg = NULL;

    int arg_len, argc = ZEND_NUM_ARGS( );

    if (zend_parse_parameters(argc TSRMLS_CC, "s/", &arg, &arg_len) == FAILURE)

        return;

    <?php

     $a = "Hello World";

     $b =& $a;

    ?>

    PHP_FUNCTION(foo) {

        long n;

        zval *val;

        int argc = ZEND_NUM_ARGS( );



        if (zend_parse_parameters(argc TSRMLS_CC, "lz", &n, &val) == FAILURE)

            return;



        SEPARATE_ZVAL(&val);

        array_init(return_value);



        while(n--) {

            zval_add_ref(&val);

            add_next_index_zval(return_value, val);

        }

    }

    PHP_FUNCTION(foo)

    {

        zval *var;



        MAKE_STD_ZVAL(var);

        Z_LVAL_P(var)=99;

        Z_TYPE_P(var)=IS_LONG;



        ZEND_SET_SYMBOL(EG(active_symbol_table), "foo", var);

    }

    #define IS_NULL               0

    #define IS_LONG               1

    #define IS_DOUBLE             2

    #define IS_STRING             3

    #define IS_ARRAY              4

    #define IS_OBJECT             5

    #define IS_BOOL               6

    #define IS_RESOURCE           7

    #define IS_CONSTANT           8

    #define IS_CONSTANT_ARRAY     9

    PHP_INI_BEGIN( )

        STD_PHP_INI_ENTRY("foo.my_ini_setting", "0", PHP_INI_ALL, OnUpdateInt,

                          setting, zend_foo_globals, foo_globals)

    PHP_INI_END( )

    static int le_test;



    typedef struct _test_le_struct {

        char *name;

        long age;

    } test_le_struct;

    static void _php_free_test(zend_rsrc_list_entry *rsrc TSRMLS_DC) {

        test_le_struct *test_struct = (test_le_struct *)rsrc->ptr;



        efree(test_struct->name);

        efree(test_struct);

    }

    le_test = zend_register_list_destructors_ex(_php_free_test, NULL, "test",

      module_number);

    PHP_FUNCTION(my_init) {

        char *name = NULL;

        int name_len, age;

        test_le_struct *test_struct;



        if (zend_parse_parameters(ZEND_NUM_ARGS( ) TSRMLS_CC, "sl", &name,

                                  &name_len, &age) == FAILURE) {

            return;

        }

        test_struct = emalloc(sizeof(test_le_struct));

        test_struct->name = estrndup(name, name_len);

        test_struct->age = age;

        ZEND_REGISTER_RESOURCE(return_value, test_struct, le_test);

    }