毕业设计（论文）外文资料和译文.doc

成都东软学院毕业设计（论文）外文资料和译文系 别： 计算机科学与技术系 专 业： 计算机科学与技术 班级： 级1班 姓 名： 学 号： 指导教师： 二XX 年 十二 月 成都东软学院毕业设计（论文） 原文PHP/MySQL Programming for the Absolute BeginnerIf you've been watching the Web for a while you've probably noticed it is changing. When the Web first entered into the public consciousness, it was a way to distribute documents. These documents were pretty easy to make.Anybody with a weekend and a text editor could get a Web page up and running. Building a Web site in the early days was about making documents.Today the Internet is much more than that. Interesting Web sites are not simply documents; they are applications. They have much more complexity and power. You might think the Web is no longer a place for individuals or beginning programmers. Many of the software development tools available are expensive and complicated.To me, the most exciting thing about the Internet is its social implications.There is a large community that believes in powerful, easy-to-use, free software. That community has produced a number of exceptional programs, including PHP and MySQL.PHP is a powerful programming language that lets you build dynamic Web sites. It works well on a variety of platforms, and it's reasonably easy to understand. MySQL is an impressive relational data management system used to build commercial quality databases. PHP and MySQL are such powerful and easy-to-use platforms that they make Web programming accessible even for beginners.In this book, I will teach you about programming. Specifically, you will learn how to write programs on Web servers. You'll learn all the main concepts of programming languages. You'll also learn about how data works in the modern environment. You'll learn commands and syntax, but you'll also learn the process of programming.If you've never written a computer program before, this book will be a good introduction. If you're an experienced programmer wanting to learn PHP and MySQL, you'll find this book to be a gentle introduction.Programming is hard work, but it's also a lot of fun. I had a great time writing this book, and I hope you enjoy learning from it. I'm looking forward to hearing about what you can do after you learn from this book.AndyChapter 1: Exploring the PHPEnvironmentOverviewWeb pages are interesting, but on their own they are simply documents. You can use PHP to add code to your Web pages so they can do more. A scripting language like PHP can convert your Web site from static documents to an interactive application. In this chapter,you'll learn how to add basic PHP functionality to your Web pages.Specifically, you'll:Review HTML commands.Use Cascading Style Sheets to enhance your Web pages.Build HTML forms.Ensure PHP is on your system.Run a basic diagnostic of your PHP installation.Add PHP code to a Web page.Introducing the "Tip of the Day" ProgramYour first program probably won't win any Web awards, but it will take you beyond what you can do with regular HTML. Figure 1.1 illustrates the "Tip of the day" page, which offers friendly, helpful advice.Figure 1.1: The tip of the day might look simple, but it is a technological marvel, because it features html, cascading style sheets, and PHP code.Of course, you could write this kind of page without using a technology like PHP, but the program is a little more sophisticated than it might look on the surface. The tip isn't actually embedded in the Web page at all, but it is stored in a completely separate file. The program integrates this separate file into the HTML page. The page owner can change the tip of the day very easily by editing the text file that contains the tips.You'll start by reviewing your HTML skills. Soon enough, you're going to be writing programs that write Web pages, so you need to be very secure with your HTML coding. If you usually write all your Web pages with a plain-text editor, you should be fine. If you tend to rely on higher end tools like Microsoft FrontPage or Macromedia Dreamweaver, you should put those tools aside for a while and make sure you can write solid HTML by hand.IN THE REAL WORLDThe Tip of the day page illustrates one of the hottest concepts in Web programming today the content management system. This kind of structure allows programmers to design the general layout of a Web site, but isolates the contents from the page design. The page owners (who might or might not know how to modify a Web page directly) can easily change a text file without risk of exposing the code that holds the site together. As you progress through this book, you'll learn how to develop powerful content management systems, as well as a lot of other cool things.Programming on the Web ServerThe Internet is all about various computers communicating with each other. The prevailing model of the Internet is the notion of clients and servers. You can understand this better by imagining a drive-through restaurant. As you drive to the little speaker, a barely intelligible voice asks for your order. You ask for your "cholesto-burger supreme," and the bored teenager packages your food. You drive up, exchange money for the combo meal, and drive away. Meanwhile, the teenager waits for another customer to appear. The Internet works much like this model. Large permanent computers called Web servers permanently host Web pages and other information. They are much like the drive-through restaurant. Users "drive up" to the Web server using a Web browser. The data is exchanged, and the user can read the information on the Web browser.What's interesting about this model is the interaction doesn't have to stop there. Since the client (user's) machine is a computer, it can be given instructions. Commonly, the JavaScript language is used to store special instructions in a Web page. These instructions (like the HTML code itself) don't mean anything on the server. Once the page gets to the client machine, the browser interprets the HTML code and any other JavaScript instructions. While much of the work is passed to the client, there are some disadvantages to this client-side approach. Programs designed to work inside a Web browser are usually greatly restricted in the kinds of things they can do. A client-side Web program usually cannot access the user's printer or disk drives. This limitation alone prevents such programs from doing much of the most useful work of the Internet, such as database connectivity and user tracking.The server is also a computer, and it's possible to write programs designed to operate on the server rather than the client. There are a number of advantages to this arrangement:Server-side programs run on powerful Web server computers.The server can freely work with files and databases.The code returned to the user is plain HTML, which can be displayed onany Web browser.Building Basic HTML PagesThe basic unit of web development is the HTML page. This is simply a text document containing special tags to describe the data in the page. Although you might already be familiar with HTML, it makes sense to review these skills because PHP programming is closely tied to HTML.TRAP As you are beginning, I strongly urge you to use a plain text editor. You can use Notepad or one of the many free editors available. There are some exceptional free editors available on the CD-ROM that accompanies this book. Word processors usually do not save files in plain text format (which PHP and HTML require) and many of the fancy Web editors (such as FrontPage or Dreamweaver) tend to write clunky code that will really get in your way once you start to add programming functionality to it.Creating the HTML "Hello" PageHTML is mainly text. The Web author adds special markups to a text document to indicate the meaning of various elements. When a user requests a Web page, the text document is pulled from the Web server, and the browser interprets the various tags to determine how the document is displayed on the screen. Figure 1.2 illustrates a very simple Web page. Figure 1.2: A very basic Web page. If you look at the code for this page, you will see that it's pretty easy to understand, even if you aren't terribly familiar with HTML code.<html><head><title>Hello, World</title></head><body><center><h1>Hello, World!</h1>This is my first HTML page</center></body></html>As you can see, many words are encased in angle braces(<>). These words are called tags, and they are meant to be interpreted as instructions for the Web browser. Most tags come in pairs. For example, the entire document begins with <html>and ends with </html>The slash (/) indicates an ending tag.Each HTML document contains a head area surrounded with a <head></head>pair. The header area contains information about the document in general. It almost always contains a title, which is often displayed in the title bar of the Web browser. However, there are no guarantees. HTML tags describe the meaning of an element, not necessarily how it is to be displayed. It's up to each browser to determine how something will be displayed.The bulk of an HTML document is contained in the body, indicated with the<body></body>tags.Within the body of the HTML document, you can use tags to define various characteristics of the page. Usually you can guess at the meanings of most of the tags. For example, the <center></center>pair causes all the text between the tags to be centered (if the browser can support this feature). TRAP It's vital to understand that HTML tags are not commands to the browser as much as suggestions. This is because there are so many different types of computers and Web browsers available. It's possible that somebody might look at your Web page on a palm-sized computer or a cell phone. These devices will not be able to display information in the same way as full-size computers. The Web browser will try to follow your instructions, but ultimately, the way the page looks to the end user is not under your direct control.The <h1></h1>tags are used to designate that the text contained between the tags is a level-one (highest priority) heading. HTML supports six levels of heading, from <h1> to <h6>. You can't be exactly sure how these headings will appear in a user's browser, but any text in an <h1>pair will be strongly emphasized, and each descending head level causes the text designated by that code to have less and less emphasis. Basic TagsThere are a number of tags associated with HTML. Most of these tags are used to determine the meaning of a particular chunk of text. Table 1.1 illustrates some of these tags.Horizontal Rule Add a horizontal line to the page. Does not have an ending tag.Of course, there are many other HTML tags, but those featured in Table 1.1 are the most commonly used. Figure 1.3 illustrates several of the tags featured in Table 1.1. Figure 1.3: An HTML page containing the most common HTML tags.The source code for the basic.html document illustrates how the page was designed.<html><head><title>Basic HTML Tags</title></head>< body><h1>Basic HTML Tags</h1><h1>This is an h1 header</h1><h2>This is an h2 header</h2><h3>This is an h3 header</h3><h4>This is an h4 header</h4><h5>This is an h5 header</h5><h6>This is an h6 header</h6><center>This text is centered</center><b>This is bold</b><br><i>This is italic</i><hr></body></html>The H1through H6headers create headlines of varying size and emphasis. The <b>tag causes text to be bold, and <i>formats text in italics. Finally, the <hr>tag is used to draw a horizontal line on the page. More HTML Tags The rest of the tags shown in Table 1.1 are featured in Figure 1.4. Figure 1.4: Examples of several other basic HTML tags. The tags in more.html are used to add lists, links, and images to a Web page. The code used to produce this page looks like this:<html><head><title>More HTML Tags</title></head><body><h1>More HTML Tags</h1><h3>Ordered List</h3><ol><li>alpha</li><li>beta</li><li>charlie</li></ol><h3>Unordered List</h3><ul><li>alpha</li><li>beta</li><li>charlie</li></ul><h3>Hyperlink</h3><a href="http:/www.cs.iupui.edu/aharris">Andy's Home page</a>< h3>Image</h3><img src="silly.gif" height = 100 width = 100></body></html>HTML supports two types of lists. The <ol></ol>set creates ordered(or numbered) lists. Each element in the list set (specified by an <li></li> pair) is automatically numbered. The <ul></ul>tags are used to produce unnumbered lists. Each <li></li>element is automatically given a bullet. Hyperlinks are the elements that allow your user to move around on the Web by clicking on specially designated text. The <a></a>tag is used to designate a hyperlink. The <a>tag almost always includes an href attribute, which indicates an address. The user will be redirected to whichever address is indicated in this address when he or she clicks on the link. The text (or other html) between the <a>and </a>tags will be designated as the hyperlink. That text will appear on the page as a link (usually blue and underlined). In the more.htmlexample, I created a link to one of my home pages (http:/www.cs.iupui.edu). When the user clicks on the "Andy's Home Page" link in the browser, he or she will be transported to that page. The other feature illustrated in more.htmlis the <img>tag. This tag is used to include images into a Web page. Most browsers readily support .gifand .jpgfiles, and many now can support the newer .png format. TRICK If you have an image in some other format, or an image that needs to be modified in some way before using it in your Web page, you can use free software such as irfanView or the Gimp (both included on the CD-ROM that accompanies this book).TablesThere are many times you might be working with large amounts of information that could benefit from table-style organization. HTML supports a set of tags that can be used to build tables. These tags are illustrated in Figure 1.5.Figure 1.5: Tables can be basic, or cells can occupy multiple rows and columns.The code for the simpler table looks like this:<table border = "1"><tr><th></th><th>Monday</th><th>Tuesday</th><th>Wednesday</th><th>Thursday</th><th>Friday</th></tr><tr><th>Morning</th><td>Math</td><td>Science</td><td>Math</td><td>Science</td><td>Music</td></tr><tr><th>Afternoon</th><td>PE</td><td>English</td><td>History</td><td>English</td><td>History</td></tr></table>Tables are created with the <table></table>tags. Inside these tags, you create rows using the <tr></tr>(table row) tags. Each table row can c