Review and Outlook Changes in PHP 5.0 and Outlook for PHP 6.0_PHP Tutorial

Currently, most php(as the current mainstream development language) installations still use the php(as the current mainstream development language) version 4.x. In fact, php(as the current mainstream development language) 5.0 has been released for some time, and now php(as the current mainstream development language) 5.1.1 has just been released . If you have not upgraded to these new versions, then let us take a look at the changes in the new version of php(as the current mainstream development language), and finally discuss the changes in php(do For today’s mainstream development languages) 6 desired features.
1. PHP (as the current mainstream development language) Changes in 5.0
As a brand new version number, in php (as the current mainstream development language) 4 and php (as the current mainstream development language) 5. Most of the hype revolves around the new object model being rewritten from the ground up. php(as the current mainstream development language) version 5 is more complete and has better running performance. In php(as the current mainstream development language) 4, the object is actually just a rough data type and is referenced by value. In an attempt to maintain as much backward compatibility as possible, in PHP 5, setting zend.ze1_compatibility_mode allows compatibility with version 4 methods. Of course, PHP (as the current mainstream development language) 5 also has some backward-incompatible changes, including: · Most of the new retained keywords are related to the object model ( exception, final, php(as the current mainstream development language)_user_filter, interface, implementations, extends, public, private, protected, abstract, clone, try, catch,
throw). The two words reserved in php(as the current mainstream development language)4 no longer exist (cfunction, old_function).
·If an object has no properties, it is no longer empty. ·Now the array_merge() function only accepts arrays. 　·Classes can be declared before use (depending on the specific situation).
·get_class(), get_parent_class() and get_class_methods() can now return a case-sensitive result, whereas the previous results were all lowercase.
·strrpos() and strripos() now use the entire string. For example, var_dump(strrpos(ABCDEF, DAF)) will return int(3) in php Language)
Return bool (false)
in 5 If $_SERVER exists, it will be populated with argc and argv - this allows the CLI version to always access this data.
· When passing an invalid IP address, ip2long() returns FALSE instead of -1. · Functions defined in an include file can now be called from the main file at any time. If the file is included twice (when the function has been defined), php(as the current mainstream development language)5 will also issue a fatal error. The require_once() and include_once functions now take into account Windows size insensitivity and will only include one file at a time - even if the function is called multiple times with filenames in different cases.
　·Get rid of the warnings in the original php
(as the current mainstream development language)
4. The new php (as the current mainstream development language) 5 will throw an error when encountering an invalid string offset.

　·Tokenizer extension no longer defines the idle T_ML_COMMENT constant. Note that these seemingly many incompatible changes are actually not big, and if you want to port the original code to PHP (as the current mainstream development language) 5, It's possible to make only minimal changes to your script. php

5 provides better ways to do many things, but if your purpose is just to make the program run, then you will not encounter too many problems trouble. Other changes in php
(as the current mainstream development language)
5 are: http://www.bkjia.com/PHPjc/509122.html

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