serialize — Generates a storable representation of a value

string serialize ( mixed $value )

Generates a storable representation of a value

This is useful for storing or passing PHP values around without losing their type and structure.

To make the serialized string into a PHP value again, use unserialize().

Parameters

value

The value to be serialized. serialize() handles all types, except the resource-type. You can even serialize() arrays that contain references to itself. Circular references inside the array/object you are serialize()ing will also be stored. Any other reference will be lost.

When serializing objects, PHP will attempt to call the member function __sleep() prior to serialization. This is to allow the object to do any last minute clean-up, etc. prior to being serialized. Likewise, when the object is restored using unserialize() the __wakeup() member function is called.

Return Values

Returns a string containing a byte-stream representation of value that can be stored anywhere.

Examples

Example 2594. serialize() example

// $session_data contains a multi-dimensional array with session
// information for the current user. We use serialize() to store
// it in a database at the end of the request.

$conn = odbc_connect("webdb", "php", "chicken");
$stmt = odbc_prepare($conn,
"UPDATE sessions SET data = ? WHERE id = ?");
$sqldata = array (serialize($session_data), $_SERVER['PHP_AUTH_USER']);
if (!
odbc_execute($stmt, &$sqldata)) {
$stmt = odbc_prepare($conn,
"INSERT INTO sessions (id, data) VALUES(?, ?)");
if (!
odbc_execute($stmt, &$sqldata)) {
/* Something went wrong.. */
}
}
?>

move_uploaded_file — Moves an uploaded file to a new location

bool move_uploaded_file ( string $filename, string $destination )

This function checks to ensure that the file designated by filename is a valid upload file (meaning that it was uploaded via PHP's HTTP POST upload mechanism). If the file is valid, it will be moved to the filename given by destination.

This sort of check is especially important if there is any chance that anything done with uploaded files could reveal their contents to the user, or even to other users on the same system.

Parameters

filename

The filename of the uploaded file.

destination

The destination of the moved file.

Return Values

If filename is not a valid upload file, then no action will occur, and move_uploaded_file() will return FALSE.

If filename is a valid upload file, but cannot be moved for some reason, no action will occur, and move_uploaded_file() will return FALSE. Additionally, a warning will be issued.

Notes

Note: move_uploaded_file() is both safe mode and open_basedir aware. However, restrictions are placed only on the destination path as to allow the moving of uploaded files in which filename may conflict with such restrictions. move_uploaded_file() ensures the safety of this operation by allowing only those files uploaded through PHP to be moved.

Warning

If the destination file already exists, it will be overwritten.

basename — Returns filename component of path

string basename ( string $path [, string $suffix] )

Given a string containing a path to a file, this function will return the base name of the file.

Parameters

path

A path.

On Windows, both slash (/) and backslash (\) are used as directory separator character. In other environments, it is the forward slash (/).

suffix

If the filename ends in suffix this will also be cut off.

Return Values

Returns the base name of the given path.

$path = "/home/httpd/html/index.php";
$file = basename($path); // $file is set to "index.php"
$file = basename($path, ".php"); // $file is set to "index"
?>

glob-Find pathnames matching a pattern

array glob ( string $pattern [, int $flags] )

The glob() function searches for all the pathnames matching pattern according to the rules used by the libc glob() function, which is similar to the rules used by common shells.

Parameters

pattern

The pattern. No tilde expansion or parameter substitution is done.

flags

Valid flags:

  • GLOB_MARK - Adds a slash to each item returned
  • GLOB_NOSORT - Return files as they appear in the directory (no sorting)
  • GLOB_NOCHECK - Return the search pattern if no files matching it were found
  • GLOB_NOESCAPE - Backslashes do not quote metacharacters
  • GLOB_BRACE - Expands {a,b,c} to match 'a', 'b', or 'c'
  • GLOB_ONLYDIR - Return only directory entries which match the pattern
  • GLOB_ERR - Stop on read errors (like unreadable directories), by default errors are ignored.

Return Values

Returns an array containing the matched files/directories, an empty array if no file matched or FALSE on error.

glob

glob — Find pathnames matching a pattern

Description

array glob ( string $pattern [, int $flags] )

The glob() function searches for all the pathnames matching pattern according to the rules used by the libc glob() function, which is similar to the rules used by common shells.

Parameters

pattern

The pattern. No tilde expansion or parameter substitution is done.

flags

Valid flags:

  • GLOB_MARK - Adds a slash to each item returned
  • GLOB_NOSORT - Return files as they appear in the directory (no sorting)
  • GLOB_NOCHECK - Return the search pattern if no files matching it were found
  • GLOB_NOESCAPE - Backslashes do not quote metacharacters
  • GLOB_BRACE - Expands {a,b,c} to match 'a', 'b', or 'c'
  • GLOB_ONLYDIR - Return only directory entries which match the pattern
  • GLOB_ERR - Stop on read errors (like unreadable directories), by default errors are ignored.

Return Values

Returns an array containing the matched files/directories, an empty array if no file matched or FALSE on error.

ini_set()

string ini_set ( string $varname, string $newvalue )
Sets the value of the given configuration option. The configuration option will keep this new value during the script's execution, and will be restored at the script's ending.

PHP Objects

Basic Object-oriented programming functionality was added in PHP 3. Handling of objects was completely rewritten for PHP 5, allowing for better performance and more features. In previous versions of PHP, objects were handled like primitive types. The drawback of this method was that the whole object was copied when a variable was assigned, or passed as a parameter to a method. In the new approach, objects are referenced by handle, and not by value. PHP 5 introduced private and protected member variables and methods, along with abstract classes and abstract methods. It also introduced a standard way of declaring constructors and destructors similar to that of other object-oriented languages, such as C++, and an exception handling model similar to that of other programming languages.
The static method and class variable features in Zend Engine 2 do not work the way some expect. There is no virtual table feature in the engine, so the static variables are bound with a name at compile time instead of with a reference.
class foo extends bar
{
function __construct()
{
}
public static function thisstaticfunc()
{
}
}
The above very basic example shows how to define a class, foo, that inherits from class bar. Additionally, the function, mystaticfunc, is a public static function that is called with foo::thisstaticfunc();.
If the developer asks to create a copy of an object by using the reserved word clone, the Zend engine will check if a __clone() method has been defined or not. If not, it will call a default __clone() which will copy all of the object's properties. If a __clone() method is defined, then it will be responsible for setting the necessary properties in the created object. For convenience, the engine will supply a function that imports all of the properties from the source object, so that they can start with a by-value replica of the source object, and only override properties that need to be changed

PHP Data types

PHP stores whole numbers in a platform-dependent range. This range is typically that of 32-bit signed integers. Integer variables can be assigned using decimal (positive and negative), octal and hexadecimal notations. Real numbers are also stored in a platform-specific range. They can be specified using floating point notation, or two forms of scientific notation.
PHP has a native Boolean type, named "boolean", similar to the native Boolean types in Java and C++. Using the Boolean type conversion rules, non-zero values can be interpreted as true and zero as false, as in Perl.
The null data type represents a variable that has no value. The only value in the null data type is NULL.
Variables of the "resource" type represent references to resources from external sources. These are typically created by functions from a particular extension, and can only be processed by functions from the same extension. Examples include file, image and database resources.
Arrays support both numeric and string indices, and are heterogeneous. Arrays can contain elements of any type that PHP can handle, including resources, objects, and even other arrays. Order is preserved in lists of values and in hashes with both keys and values, and the two can be intermingled

PHP Command-line scripting

PHP also provides a command line interface SAPI for developing shell and desktop applications, daemons, log parsing, or other system administration tasks. PHP is increasingly used on the command line for tasks that have traditionally been the domain of Perl, Python, awk, or shell scripting

PHP Server-side scripting

Originally designed to create dynamic web pages, PHP's principal focus is server-side scripting. While running the PHP parser with a web server and web browser, the PHP model can be compared to other server-side scripting languages such as Microsoft's ASP.NET system, Sun Microsystems' JavaServer Pages, mod_perl and the Ruby on Rails framework, as they all provide dynamic content to the client from a web server. To more directly compete with the "framework" approach taken by these systems, Zend is working on the Zend Framework - an emerging (as of June 2006) set of PHP building blocks and best practices; other PHP frameworks along the same lines include CakePHP, PRADO and Symfony.
The LAMP architecture has become popular in the Web industry as a way of deploying inexpensive, reliable, scalable, secure web applications. PHP is commonly used as the P in this bundle alongside Linux, Apache and MySQL, although the P can also refer to Python or Perl. PHP can be used with a large number of relational database management systems, runs on all of the most popular web servers and is available for many different operating systems. This flexibility means that PHP has a wide installation base across the Internet; over 19 million Internet domains are currently hosted on servers with PHP installed

PHP Usage

PHP generally runs on a web server, taking PHP code as its input and creating Web pages as output. However, it can also be used for command-line scripting and client-side GUI applications. PHP can be deployed on most web servers and on almost every operating system and platform free of charge. The PHP Group also provides the complete source code for users to build, customize and extend for their own use.
PHP primarily acts as a filter. The PHP program takes input from a file or stream containing text and special PHP instructions and outputs another stream of data for display.
From PHP 4, the PHP parser compiles input to produce bytecode for processing by the Zend Engine, giving improved performance over its interpreter predecessor. PHP 5 uses the Zend Engine II.

PHP History

PHP was written as a set of CGI binaries in the C programming language by the Danish/Greenlandic programmer Rasmus Lerdorf in 1994, to replace a small set of Perl scripts he had been using to maintain his personal homepage.[4] Lerdorf initially created PHP to display his résumé and to collect certain data, such as how much traffic his page was receiving. Personal Home Page Tools was publicly released on 8 June 1995 after Lerdorf combined it with his own Form Interpreter to create PHP/FI (this release is considered PHP version 2).[5]
Zeev Suraski and Andi Gutmans, two Israeli developers at the Technion IIT, rewrote the parser in 1997 and formed the base of PHP 3, changing the language's name to the recursive initialism PHP: Hypertext Preprocessor. The development team officially released PHP/FI 2 in November 1997 after months of beta testing. Public testing of PHP 3 began and the official launch came in June 1998. Suraski and Gutmans then started a new rewrite of PHP's core, producing the Zend Engine in 1999.[6] They also founded Zend Technologies in Ramat Gan, Israel, which actively manages the development of PHP.
In May 2000, PHP 4, powered by the Zend Engine 1.0, was released. The most recent update released by The PHP Group, is for the older PHP version 4 code branch which, as of May 2007, is up to version 4.4.7. PHP 4 will be supported by security updates until 8 August 2008[7].
On July 13, 2004, PHP 5 was released powered by the new Zend Engine II. PHP 5 included new features such as:[8]
Improved support for object-oriented programming
The PHP Data Objects extension, which defines a lightweight and consistent interface for accessing databases
Performance enhancements
Better support for MySQL
Embedded support for SQLite
Integrated SOAP support
Data iterators
Error handling via exceptions