You want to extract part of a string, starting at a particular place in the string

Use substr( ) to select your substrings:

$substring = substr($string,$start,$length);
$username = substr($_REQUEST['username'],0,8);

Read More

Php get_meta_tags-Extracts all meta tag content attributes

get_meta_tags — Extracts all meta tag content attributes from a file and returns an array

<?php// Assuming the above tags are at www.example.com$tags = get_meta_tags('http://www.example.com/');
// Notice how the keys are all lowercase now, and
// how . was replaced by _ in the key.echo $tags['author'];       // nameecho $tags['keywords'];     // php documentationecho $tags['description'];  // a php manualecho $tags['geo_position']; // 49.33;-86.59?>

Read More

PHP Redirect - Redirect Script?

PHP Redirect Function

header('Location:  destination.php');
exit();

ou need the Location: part so the browser knows what header it's 

receiving. Also, don't forget to 

do an exit() or die() right after the redirect. 

 

Read More

Control Structures

• if
• else
• elseif/else if
• Alternative syntax for control structures
• while
• do-while
• for
• foreach
• break
• continue
• switch
• declare
• return
• require
• include
• require_ once
• include_ once
• goto

Read More

Finding the Position of a Value in an Array

Use array_search( ) . It returns the key of the found value. If the value is not in the array, it returns false:

$position = array_search($value, $array);
if ($position !== false) {
    // the element in position 

//$position has $value as its 

//value in array $array
}

Use in_array( ) to find if an array contains a value; use array_search( ) to discover where that value is located. However, because array_search( ) gracefully handles searches in which the value isn't found, it's better to use array_search( ) instead of in_array( ). The speed difference is minute, and the extra information is potentially useful:

$favorite_foods = array(1 => 'artichokes', 'bread', 'cauliflower', 'deviled eggs');
 $food = 'cauliflower'; $position = array_search($food, $favorite_foods);
 if ($position !== false)
{
echo "My #$position favorite food is $food";
}
 else {
 echo "Blech! I hate $food!";
 }

Use the !== check against false because if your string is found in the array at position 0, the if evaluates to a logical false, which isn't what is meant or wanted.

If a value is in the array multiple times, array_search( ) is only guaranteed to return one of the instances, not the first instance.

Read More

Turning an Array into a String

convert it into a  formatted string.

Use join( ):

// make a comma delimited list
$string = join(',', $array);

Or loop yourself:

$string = '';

foreach ($array as $key => $value) {
    $string .= ",$value";
}

$string = substr($string, 1); // remove leading ","

If you can use join( ), do; it's faster than any PHP-based loop. However, join( ) isn't very flexible. First, it places a delimiter only between elements, not around them. To wrap elements inside HTML bold tags and separate them with commas, do this:

$left = '<b>'; $right = '</b>'; $html = $left . join("$right,$left", $html) . $right;

Second, join( ) doesn't allow you to discriminate against values. If you want to include a subset of entries, you need to loop yourself:

$string = ''; foreach ($fields as $key => $value) { // don't include password if ('password' != $key) { $string .= ",<b>$value</b>"; } } $string = substr($string, 1); // remove leading ","

Read More

Setting Environment Variables

Setting environment variables in your server configuration
on a host-by-host basis allows you to configure virtual hosts differently.

<?php
putenv('ORACLE_SID=ORACLE'); // configure oci extension
?>

Adjusting behavior based on an environment variable

 <?php
$version = $_SERVER['SITE_VERSION'];

// redirect to http://guest.example.com, 

//if user fails to sign in correctly
if ('members' == $version) {
    if (!authenticate_user($_POST['username'], $_POST['password'])) {
        header('Location: http://guest.example.com/');
        exit;
    }
}
include_once "${version}_header"; // load custom header

http://www.php.net/putenv; information on setting environment 
variables in Apache at 

Read More

Extracting Substrings

You want to extract part of a string, starting at a particular place in the string. For example, you want the first eight characters of a username entered into a form.

 Extracting a substring with substr( )

<?php
$substring = substr($string,$start,$length);
$username = substr($_GET['username'],0,8);
?>

If $start and $length are positive, substr( ) returns 
$length characters in the string, starting at $start.

If $start is bigger than the length of the string, substr( ) returns false..

Read More

Setting Default Values for Function Parameters

Assign the default value to the parameters inside the function prototype:

function wrap_html_tag($string, $tag = 'b') {
    return "<$tag>$string</$tag>";
}

The example in the Solution sets the default tag value to b, for bold. For example:

$string = 'I am some HTML'; wrap_html_tag($string);

returns:

<b>I am some HTML</b>

This example:

wrap_html_tag($string, 'i');

returns:

<i>I am some HTML</i>

There are two important things to remember when assigning default values. First, all parameters with default values must appear after parameters without defaults. Otherwise, PHP can't tell which parameters are omitted and should take the default value and which arguments are overriding the default. So wrap_html_tag( ) can't be defined as:

function wrap_html_tag($tag = 'i', $string)

If you do this and pass wrap_html_tag( ) only a single argument, PHP assigns the value to $tag and issues a warning complaining of a missing second argument.

Second, the assigned value must be a constant, such as a string or a number. It can't be a variable. Again, 

using wrap_html_tag( ), such as our example, you can't do this:

$my_favorite_html_tag = 'i'; function wrap_html_tag($string, $tag = $my_favorite_html_tag) { ... }

If you want to assign a default of nothing, one solution is to assign the empty string to your parameter:

function wrap_html_tag($string, $tag = '') { if (empty($tag)) return $string; return "<$tag>$string</$tag>"; }

This function returns the original string, if no value is passed in for the $tag. Or if a (nonempty) tag is passed in, it returns the string wrapped inside of tags.

Depending on circumstances, another option for the $tag default value is either 0 or NULL. In wrap_html_tag( ), you don't want to allow an empty-valued tag. However, in some cases, the empty string can be an acceptable option. For instance, join( ) is often called on the empty string, after calling file( ), to place a file into a string. Also, as the following code shows, you can use a default message if no argument is provided but an empty message if the empty string is passed:

function pc_log_db_error($message = NULL) { if (is_null($message)) { $message = 'Couldn't connect to DB'; } error_log("[DB] [$message]"); }

Read More

CuteNews right

Additional X-Field, ability to see the first posts while adding and editing,
 PHP-code error protection while news output, error logging at backend.

A notable feature of the CuteNews engine is that it doesn't use MySQL to store news,
comments, user profiles, or any other data.
The CuteNews engine can be installed on practically any web server.

CuteNews allows for different types of users with different permission levels: Administrator, Editor, Journalist, Commenter. Each of these types of users has access to different features on a
CuteNews-driven website.

You don't have to worry about creating news items: CuteNews does everything automatically. It is also capable of archiving old news items and activating postponed ones on its own.

Download Cute News 1.5.2 zip (570 Kb)

Read More