First section Introduction _php

Introduction

　　PHP is a server-side scripting language that is easy to learn and use. With minimal programming knowledge, you can use PHP to build a truly interactive WEB site. This tutorial does not want you to fully understand the language, but it will allow you to join the development of dynamic Web sites as soon as possible. I assume you have some basic knowledge of HTML(or HTML Editor) and some programming ideas.

1. Introduction

php is one of the tools that allows you to generate dynamic Web pages. php represents: Hypertext Preprocessor (php:hypertext preprocessor ). php is completely free of charge, you can php official site free download. php complies with gnu Public License (GPL) , Under this license are many popular software such as linux and emacs . You can gain unlimited access to the source code and even add the features you need. php in most unix platform, gun/linux and Microsoft windows can be run on the platform. How to install lang= on windows environment pc "en-US" machine or lang= >unix "en-US" machine Lang= "en-US" >php information can be found on the official site of php , you can also refer to the Web Page Pottery bar "php Installation full-featured article. The installation process is simple.

If your machine solves the problem , then PHP does not have the millennium bug problem!

1.1 history

Three years ago,Rasmus Lerdorf Created to create his online CV"Personal page Tools"（Personal Home Page Tools）。 This is a very simple language. A growing number of people subsequently took note of the language and made various suggestions for its expansion. In the selfless devotion of many people and the free nature of the source code of the language itself, it has evolved into a rich language and is now growing.PHPAlthough it is easy to learn, but faster thanMod_perl(implantedWebServer'sPerlmodule) is slow. Now we have the ability toMod_perlSpeed to rival is calledZendThe new engine, andPHP4Can make the most of the engine. Right nowPHP4The official version has been released and everyone can go toPHPOfficial site to download.Andy Gutmans AndZeev Suraki IsZend's main author. can go toZendSite(http://www.zend.com)Learn more.

　　The application of PHP has grown significantly in the personal Web project. According to Netcraft 's report in 1999 , there are 931122 domains and 321128 IP addresses to use PHP Technology.

1.2 PHP the Advanced place

There are many benefits to applying PHP . Of course, the disadvantage is that PHP is not commercially supported because it is an open source project, and the resulting execution speed is slow (until PHP4 ). But PHP 's mailing lists are very useful and unless you're running a popular site like yahoo ! or Amazon.com , you won't feel the speed of PHP being any different. At least I didn't feel it! Well, let's take a look at the advantages of PHP :

- learning process

I personally prefer PHP 's very simple learning process. Unlike Java and Perl , you don't have to learn to write a decent program without burying your head in a document that is more than one page. As long as you know some basic grammar and language features, you can start your PHP coding journey. You can then go through the documentation if you are having trouble with the coding process.

　　PHP 's syntax is similar to C,Perl,ASP , or JSP. For those who are more familiar with one of these languages,PHP is too simple. Conversely, if you know more about PHP , you will be very easy to learn from several other languages.

You can get all the core language features of PHP in as little as five minutes, you probably already know the HTMLvery well, and you've even learned how to make a good-looking WEB site with an editorial design software or by hand. Because PHP code can be easily added to your site, while you design and maintain the site, you can easy to join PHP to make your site more dynamic features.

- database connection

　　PHP can be compiled into functions that are connected to many databases. PHP and MySQL are now a great combination. You can also write your own peripheral functions to access the database indirectly. With this approach, you can easily change the encoding to accommodate such changes when you replace the database you are using. Phplib is the most common set of base libraries that can provide general transaction needs.

- Scalability

As I said earlier,PHP has entered a period of rapid development. It may be difficult for a non-programmer to extend additional functionality to PHP , but it is not difficult for a PHP programmer.

- Object-oriented programming

　　PHP provides classes and objects. Web -based programming requires an object-oriented programming capability. PHP supports constructors, extraction classes, and so on.

- Scalability

Traditionally, the interaction of Web pages is achieved through CGI . The CGI program's scalability is not ideal because it opens a separate process for each of the running CGI programs. The solution is to compile the interpreter for the language that is often used to write CGI programs into your Web server ( such as mod_perl,jsp). PHP can be installed in this way, although few would like to install it in a CGI manner. Built-in PHP can be more scalable.

- more features

　　PHP Developers have developed many of the most popular base libraries for Web programming, which contain easier-to-use layers. You can use PHP to connect most databases, including Oracle,ms-access, andMysql . You can draw pictures on flies, write programs to download or display e-mails. You can even complete network-related functions. Best of all, you can choose which features you need for your PHP installation. Quoting Nissan 's Xterra , PHP can do everything you want it to do and be omnipotent !

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