Http://www.netqu.com China Technical Network Member Wuxuehui Released

Translation: Chen zhihong Editor: Sun Yizhong

These days, almost everyone is talking about XML (Extensible Markup Language), but few people really understand their meaning. XML's advocator believes that it can solve all HTML unable to solve problems, allowing data to be flexibly exchanged between different operating systems or applications. Indeed, all observers agreed that XML will trigger a revolution in content publishing and knowledge exchange. Who will enter this field, who will be able to gain a lot.

The 20 popular issues here will make you an XML "expert" or at least let you see the development direction of XML in the future.

1 What is XML? 11 OSD and CDF relationships with XML? 2 xml What is important? 12 E-Commerce and XML? 3 SGML, HTML and XML? 13 XML stacking style? 4 How to implement XML? 14 XML How to improve hyperlink? 5 What is the file type definition (DTD)? 15 Server support XML? 6 What is a full and effective file? 16 Who should learn XML? 7 How to read XML in your browser? 17 What are you writing XML tools for me? 8 RDF and XML? 18 XML Internationalization? How to implement XML? 19 XML in the NetScape browser? Where? How to implement XML? 20 Where can I achieve more XML knowledge in the 10 Microsoft browser? 1. What is XML? XML represents the extension language (Extensible Markup Language). Head by World Wide Web Consortium (W3C), XML becomes a formal specification in the mid-February. XML developers will tell you XML is not a language, but a system that defines other languages. You may have heard of it, or have used these languages, - If Microsoft supports "promoting technology" Channel Definition Format (CDF). W3C is engaged in XML-related recommendations, saying that XML is "common syntax" in the structure of data. "Structured data refers to its content, meaning Or apply the marked data. For example, the

tag specifies that the text is a font and size, and the XML tag will clearly determine the type of information: tag can identify the author of the document, tag can be A inventory list contains the cost of a project. By separating the structure, content, and manifestation, the same XML source document is only written once, you can use different ways to manifest: on your computer screen, on your mobile phone display, Translated into voice into the device of the blind service, and so on. It works on any communication product that may be developed. An XML document can have a longer than the author and display technology when it is written. So, XML will not be limited to Internet, for example, you can serve the entire publishing industry, especially those who want to make documents that can appear on a variety of media. Some large document publishers who use Standard Generalized Markup Language (SGML) will turn to XML. Also, The XML of the platform is developed for web, which is the most influential place. Domxml's true power is how it is interacting with Document Object Model (DOM). Interface. Using DOM, programmers can write dynamic content with a standard method. In other words, they can use it to make some specific contents in the browser document tree, for example, producing a small effect When the user moves the mouse to the text, these texts become blue. Netscape Navigator and Microsoft Internet Explorer have their respective DOM, but they all call W3C standard DOMs in its next version browser. 2.xml What is important? The saying of the web leader is the content. Unfortunately, the content is often combined with its performance. How many times have you encounter a small tip on a website, "best at 800x600 pixels Solution display "

• XML will help solve the above problems because the website builders don't have to specify what to show, but to indicate the structure of the document. For example, you can explain the title of the document, the author, the associated document, and so on, then any one Equipment with XML browser can give a version version that is best for it, such a device can be a handheld computer, a top box, or a high-speed workstation. However, perhaps XML's best feature is its intrinsic scalability Company and organizations can expand XML to meet new challenges and applications. A XML-based language is already in use - Microsoft Channel Definition Format (CDF) - More will appear, including Resource Definition Format (RDF) and Open Software Description (OSD). XML also allows a standard mechanism for exchange data and documentation. For example, XML may become a method of exchange information on different vendors' databases on the Internet. Nowadays, there are still some mornings that accurately determine the direction of XML. However, the possibility is awesome, which is why there is an important reason why XML has so much excitement. << Back to title 3. SGML, HTML and XML? < Standard Generalized Markup Language (SGML) is a way to express data in text processing applications. It has been more than ten years, and XML and HTML are developed from SGML. Therefore, they all have a common point. As used as a similar syntax and the use of markers with arc. But HTML is an application of SGML, and XML is a subset of SGML. The difference is important. Basically HTML cannot be used to define new applications, and XML can. For example, Resource Description Format (RDF) and Channel Description Format (CHANEL DESCRIPTION format (CDF) are applications using XML definitions. XML and HTML are more like a brother, not a brother. In fact, XML and SGML are compatible - XML ​​documentation Read any SGML production or browse tools. However, XML does not have SGML so complicated, it is a network designed for limited bandwidth, such as Internet. XML specification collaborator Tim Bray said that XML's design starting point is the advantage of using SGML, Remove complex parts, keep it lightweight, you can work on the web. HTML, SGML, and XML will continue to be used for its right place, any of them will not make other discards. HTML is still rapidly published on the Web The simplest method of data, most short-term data, such as meeting agenda or advertising brochures. If the data will be used for a long time, and more structures need, the web builder will be willing to use XML. Different from HTML and XML, SGML May never be widely accepted on the Internet, because it has never been designed or optimized for a network protocol. For high-end, complex structural publishing applications, SGML will continue to apply. 4. How to implement XML? XML Will be applied in a variety of different ways. One is exchanged between the human machine, such as a browser from the web server to the user. The other is exchanged data between different applications, or exchange data between machines. In these cases, you may need a three-layer architecture: the backend database, the intermediate layer server for the processing logic of the data, and the client that further displays and processes the client. The database can receive information from multiple data sources, which may already be XML Format data. The intermediate layer then gathers data and publishes on the final performance layer. Now, the webpage is sometimes transmitted from the NEWS.com in this approach to publish data from a database. But to get a new page View, such as News.com's new "printer friendly" option, The server must generate a new page. A properly formatted XML document will allow the client to modify the representation of the document in different media, such as printers. <<

Returning Title 5. What is the DTD? Document Type Definition (DTD) is a set of syntax rules for markers. It tells you which markers can be used in the documentation, what should they appear in what markers can appear in other In the tag, which tag is attribute, and so on. DTD is originally developed to use SGML, which can be part of the XML document, but it is usually a separate document or a series of documents because XML itself is not a language Instead, it defines a system in language. It has a universal DTD like HTML. Instead, industrial or organization wants to use XML to exchange data exchanged industrial or organizations can define their own DTD. If an organization wants to use XML to identify only internally With documentation, it can create your own private DTD. For example, Wall Street Journal Interactive Edition has a DTD to explain each version in detail, in which information is subject to page, articles, summary, title, etc. Publications currently use SGML DTD (Known as DOW Jones Markup Language), but it is also developing an XML version. About DTD is not no dispute. Some people feel that it adds a real value to the business business, and some people feel that it limits creativity. Some people think that DTD is useful, but it is not enough. Microsoft is trying to use its XML data proposal to solve the previous complaint, but the critics say that these improvements should be carried out in the DTD specification itself. Microsoft's SCHEMA some suppliers, including Microsoft has proposed a method of replacing DTD, called Schema. They have submitted them to W3C with XML data. As with DTD, Schema provides the rules of the document, and point out what tag, marker properties, Connection, etc .. However, different from DTD, Schema can define data types. For example, DTD may have a tag , and the content between the marker can be a digital or string. Schema can specify only only Enter numbers. This method obviously has its advantages, especially for data transmission between applications, objects, or databases. The only problem is that it will become a DTD specification, or an extension of XML. 6. What is complete and effective? File? There are basically two types of related XML documents: constructive and effective. Construct good XML document compliance with the general rules of XML syntax, these rules are more stringent than HTML and SGML. XML character data will never Live there, there is no end identifier, or like to end the end identifier appearing, or a special Other empty elements markers with a slash before the right angular arc, such as the ; XML logo always in the left parentheses or start; element type and attribute name are case-sensitive; attribute requires quotation mark; Wait. Effective XML document complies with a particular document type definition (DTD). Verify that the work of the correctness of XML documents is mainly borne by the production publishing tool, and the XML browser is to read the XML document, just check the good construct Sex. In this way, the parser in the production tool has to check the construction of goodness and effectiveness, while the browser only considers XML that has been constructed. <<

Returns the title 7 How to read the XML in your browser? Tools for reading the XML document are generally called an XML parser, although it is more formal name being an XML processor. The XML processor transmits the data to the application to make production, publication, Query, or display. XML does not provide an application interface (API) to the application, it just transmits the data to the application. The XML processor does not parse the non-constructed data. Netscape and Microsoft have included the XML parser In the browser, or is planning to include it into the browser. XML developer group provides free XML reader and parser to apply to application software or XML production software: Textuality's lark, one of the author of XML specification Microstar Software's æLFRED, a Java-based parser. Datachannel's DXP, predecessor is a famous NXP, or has added API's NORBERT (Mikula) XML parser. 8 RDF and XML What does it contact? If XML is said The ability of the language, the XML application software is a specific language. Resource Description Format RDF is an application software: a data modeling language using an XML syntax. RDF is a method describing and accessing data. This means RDF is data about data, or metadata. In the web, these metadata will be used to establish standard site maps, more precise search results, and hierarchical topic indexes. RDF also allows smart bookmarks, When the indexed web page changes, the bookmark changes. If you track the site regularly updated sites, such as the CNET's news.com, it will be useful. For website builders, establish the contents of its website referenced by the search engine Data is not difficult. We will soon have commercial software, which will generate RDF files for a given site. XML metadata will also active market markets. There are many rating agencies to appear online, they evaluate everything Data, from the site to protect your child's safety to the best movie or wine site. RDF describes the syntax of the rating mechanism can use. People will choose the rating agency who feel the most suitable vocabulary, the vocabulary means Special set of terms used by different types of content rating - from sex and violence to vintage acidity. << Back to Title 9 Netscape browser How to implement XML? Netscape will deliver a coded Aurora in Communicator / Navigator 5.0 To support XML metadata. Aurora Use RDF to get Netscape "Desktop Information Full Integration." Aurora Find and Manage Information between Network, Desktop, and Database. It will appear on the desktop with the "Window" menu, will gather to point to current project, research The ame, or a pointer such as daily activities. RDF makes the Aurora's navigation bar points to the local files of different data types (text processing documents, table data, email messages, database content), also point to resources on the Internet or intranet server (search And query results, bookmark links, etc.). A XML parser reads RDF will be part of the Netscape 5.0 browser and will appear in a beta before the final product delivery. In addition to this initial RDF Realization, Netscape is planning to include a universal XML parser in your browser, while its browser can work with other XML applications, such as Shakespeare Markup (an early XML application), Chemical Markup Language (CML) , And Mathml, a mathematical logo language that is recommended for W3C. "We must make Navigator a XML platform," Netscape principle engineer RV Guha said. Guha has developed MCF (MCF), MCF has been added RDF specification. 10 How to implement XML in the Microsoft Browser? Microsoft Internet Explorer 4.0 is the first web browser that implements XML. Microsoft provides a pair of XML processors: Browser is carried with C

Write the parser, and a web buffer can download and join the source code of the Java parser of their own application. Java parser is a valid parser, that is, it defines (DTD) according to a document type (DTD) or Schema is checked. In order to improve performance, the C version of the browser is a non-active parser. According to Microsoft's product manager Steve Sklepowich, these two parsers are "universal" because they It does not rely on specific XML applications, such as Channel Definition Format. Due to XML data and its performance separation, the ability to actually display XML in a web browser itself requires style sheet, such as XSL (Extensible Style Language). At the same time, Microsoft uses it The XML Data Source Object, or called XML DSO. It applies dynamic HTML data bundled capabilities, links one end XML data and the other end HTML data. (About data bundle, you can view builder.com Browser Playground.) IE 4.0 Access the XML document, querying the data, and then displayed as HTML. Microsoft also uses XML Object Model (XML OM) to interact with XML data in the browser. It is through HTML acts as an object based on Document Object Model (DOM), although HTML and DOM are not directly compatible. DOM allows scripts and programs to access structured XML data. Sklepowich said, although current in Microsoft, XML will be in browser, XML will The final appears in "any HTML has already appeared". CEO Bill Gates has publicly announced that Microsoft Office will support XML, and the company also plans to support email packages and standards for making XML tools. <<

Returns the relationship between OSD and CDF and XML? Channel Definition Format (CDF), and Open Software Description (OSD) are two XML applications supported by Microsoft. By reading CDF files through its XML parser, Microsoft's Internet Explorer 4.0 reads CDF files to drive And control the page brought by the PUSH channel. According to the work made with Resource Definition Format (RDF), the CDF proposes to give the W3C recently to use the RDF's ability to display the connection between different data elements. Open Software Description is a vocabulary for describing software components, with grammar such as subordinate, versions, and platforms. OSD describes how to represent the characteristics of a component, and how to install the part to your computer. It can be used to download a complete package It is mainly designed for increasing updates. OSD works separately or works together with CDF to define applications. OSD recommends a group of vendors led by Microsoft and Marimba from August 1997 to W3C.12 e-commerce (E-Commerce) and XML? For four years, Commercenet, this non-profit online business association with 500 members is working hard to work with E-Commerce products and systems. The concept is to allow information between different directories, Spending from the catalog to the payment system, exchange between payment systems. XML has been discovered to help implement the above concepts in two important aspects: content definitions and information exchange. Content definition: CommerceN is defining data elements for multiple business transactions. This Something called Commerce Core will define things to give things such as company name, address, price, terms and quantities. Information exchange: open, text-based XML is ideal for exchange transaction information between servers. CommerceNet proposes XML's Common Business Language (CBL) to describe the product and service directory software, metadata of business rules and systems, and software for forms and messages. Many CBLs are taken from the existing Electronic Data Interchange (EDI) dictionary, EDI Dictionary Identification Specific terms such as invoices and purchase orders. But CBL surpassing EDI commercial - commercial focus, contains retail transactions and landscape supply chains - from suppliers to wholesalers to retailers. One such CBL application is In order to enable directory Information Exchange (PIX) Specification. CommerceNet design PIX to help suppliers and their distributors more easily exchange product data. Long-term goals are industrial organizations - not Commercenet, as a common CBL as a specific DTD Basic use. Some preliminary attempts focusing on industries have announced: Open Buying on The Internet (OBI): A standard of international business shopping on the Internet. OBI is based on current Internet standards such as HTML, SSL (for Security), SET (for credit card transactions), and X.509 (for digital authentication). OBI supporters include Commerce ONE, Connect, InteliSys, Interworld, Microsoft, Netscape, Open Market, and Oracle. Open Trading Protocol (OTP) : A common environment that can be operated on the Web. The rules will include from how to reduce the price, payment choices, product transportation, reception, and problem solving. OTP by Mastercard International, Digicash, Cybercash, Hewlett-Packard, IBM, AT &

T Uneiversal Card, Netscape, Royal Bank of Canada, and Some Other Financial Institutions and Technologies Support. Internet Content and Exchange (Ice): Vignette, Firefly Network, and Some companies - including Microsoft - developing a called ICE The specification, enabling an online asset that can be exchanged between sites, whether it is content, application, or metadata. ICE will use existing standards, including OPS / P3P (to make personal data reliable exchange), CDF, OSD , XML-DATA, and RDF. << Returns the stacking style in the title 13 XML? There are three style sheets (CASCADING STYLEETS (CSS) Extensible STYLE STYE Sheets (XSL) Document Style Semantics and Specification Language (DSSSL). If the 5.0 version of the browser supports XML, XML supports existing CSS standards Most of the basic style and page issues will be dealt. However, CSS may not be strong enough for professional publishers. So, there is a DSSSL in the other end, a standard of ISO (International Standards Organization), which is popular in high-end publishers using SGML. DSSSL is complicated, it is handled by print document management, very useful on the web. Now extensible style language (XSL), STYLE-Sheet written in XML. XSL is currently handed over to W3C as a proposal It gives Web developers and users more than HTML more performance flexibility. For example, HTML's

identifier is basically the same in all browsers, but XSL allows developers to specify their page elements. Performance (although users can overwrite it in personal settings). XSL is more powerful than CSS because it makes web builders create documents that can be dynamically changed. For example, you can include such programs, "if an XML element The attribute is a value of 10, which is displayed green, otherwise it is black. "Or you can use" for internal use "as a property to a paragraph, so that it does not appear in some cases. XSL is designed for scripting language Such as JavaScript. 14 XML How to Improve Hyperlink? XML hyperlink is more new than the basic HTML-style hyperlink, including "smart" links without handwriting a lot of JavaScript code. And in XML, the link itself has become an object, It can be managed as other objects. The original link specification - xll, or XML link language - is divided into two different specifications: XPointer and XLink. XPointer: In HTML, you want to link to a page, page The author must add a positioning identifier there. Use XPointer, you can "add to" (not "connected to") any part of the other person's text. Obviously, this will help work in legal documents, science and academics Papers, even W3C specification! XLINK: When the user clicks on an HTML hyperlink, the current web page is connected to the file replacement. XLink makes the web builders add behavior to the link. For example, now, you must use some JavaScript, make it in the link A separate window is popped, but XLink allows the web builder to encode the link to perform a series of actions, including a list of pop-up selection. Another application can be a dialog box, which may be a reminder user is updating Database warnings. Link pop-up menus may require users to click on a box to indicate that they accept their obligations before further processing. Now, implement such a function to write a lot of script code. XML also allows the web builder to create an Extended Link similar to Web ring work The web ring is through "next / the front"

The line group comes to navigate the website of the same topic. For the Pop-up menu too long, the web builder can create a link table, this table will change in different sites, the page will change. Users can Click on an icon to automatically transfer to the next member in the ring. This function is now required to CGI Scripts, and Extended Links provides a standard, non-privately established resource connection method. Still more problems need to be resolved, Especially in terms of behavioral policy. It must be coordinated by a method to coordinate the following three relationships: the document author's behavior recommended by the link, the user's way of displaying link information, and when and when ignoring the user's will <<

Return to the title 15 Server supports XML? XML is designed to store the storage format for long-term use, high-value documents. XML is not only lets you define the identifier, which also allows you to define the storage structure of the document. One HTML document only In one file, an XML document can be composed of multiple files stored in different locations (called entities). This proposes the concept of XML servers as a document repository. Server software vendor is supporting XML: ENIGMA Insight 4.0 This is a professional electronic publishing software solution that provides publishers handles large documents. ENIGMA SGML / XML Style Sheet Editor, bundled with Insight, can also be provided as a separate product. Hynet Technology SystemDigital Library System (DLS) manages documents and document components as standard software objects, allowing the introduction of documents created in Adobe Framemaker and Microsoft Word, or SGML / XML files. INSO, Dynatext Professional Publishing System This is an index, search and Software for making scripts, which can operate in Microsoft Internet Information Server and Netscape Enterprise and FastTrack Servers on Windows NT 3.51 or 4.0, or Sun Solaris 2.5, Open Market, FolioPen Market, Folio 4 information management and sending products to send the product XML document Introduce the indexed database to deliver content on the IP network, or send the content to the CD-ROM. In January, Open Market announced the enhancement of XML support, allowing documents to index and ensure security in their own format. Folio products will also be able to interoperate with other solutions based on standard production, resolution, and build XML documents. Its products include Folio SiteDirector, Folio SecurePublish, and Folio Publisher (e-published) WebMethods, Web Automation ServerWeb Automation Server helps companies will browser-based applications and other applications The data is combined. It is an XML-based server that uses WebMethods to perform WIDL (Web Interface Definition Language) with Web Data between the machines. (The company has handed over to World Wide Web Consortium as a standard proposal.) 16 Who should learn XML? All web builders need enough to understand XML to decide whether to use it. E-Commerce site and the site of a large number of documents in the management database are obviously preferred objects. Manager may not need to learn XML syntax or how to build DTD, they still have to understand the potential of XML and use. If the final purpose is just letting read information, HTML can meet the requirements of identification information. But if you want to process data for automatic data, you must consider XML Incorporate your publishing system. Not every HTML producer that works in the Web site must become an XML producer, but some employees should be well connected to the XML - especially the work objects of the site are data and documents managed to manage future use. At the time. Of course, the functionality of XML also means complexity - some web builders have found that they can master HTML's basis in a few days, and they may need to spend a few weeks to adapt to XML. Only you can decide whether it is worth Flowers these times. << Back Title 17 What are the writing of XML tools for me? Fortunately, the web founders don't have to start creating XMLs all over the head. There is already created, managed and sends XML on the market. Tools, and some companies are also developing. Adobe: In the mid-1998, Adobe will introduce Framemaker and FrameMaker that can be output to XML

SGML transition version. The full version of these products will be able to enter XML. Adobe has a representative of the XML working group in W3C, and Adobe also participates in XLINK, CASCADING SHEETS and RDF, so we can expect these technologies in Adobe future The product appears. Allaire: Homesite 4.0 and Cold Fusion 4.0 are expected to have this summer, they will support XML, including Style Sheets. Homesite 3.0 has provided a CDF add-on software. Arbortext: Arbortext works in the SGML field XML Styler released XML Styler, a free Java-based XSL editor in January. Its graphical user interface allows us to edit it. In the future, Arbortext integrates XML Styler to Adept, Adept It is the company's XML production tool for printing publishing. Datachannel: a free, Java-based effective parser called DXP (Datachannel XML Parser; Based on Norbert Mikula). You can get from the company's Web site. It is newly released to the free XML toolkit, XML development environment, which includes a set of components that help people start learning and apply XML. INSO: The company provides "the company" first integrated, end-to-end, creation , Conversion, storage, management, indexing, query XML content, publishing it into a WEB, CD-ROM, and a publishing solution on the printer. "Its products include Dynatag 4.0, Dynabase 3.0, Dynatext 3.1, and the attached tool DynaWeb. INTRANET SOLUTIONS: INTRA.DOC Management System's next version, IntraNet Solution web-based document management system will manage relations between XML components and documents, provide integrated link management, and third-party XML production tools, perfect in browsing The use of XML objects in the device and provides a metadata model between the Intra.Doc repository and the XML editor. Microsoft: Microsoft hopes to deliver Office 9.0 at the end of the year, reported, it will have an XML support. Microstar : ActiveSG / XML is a set of transaction-based XMs on the Internet The tool and technology of the L / SGML system. Microstar also offers a free æLFred XML parser. Softquad: HTML Editor HotMetal Pro will soon provide Live Data Base Pages, one lets developers pull HTML data into the database and come in XML The additional software returned. Vignette: StoryServer 3.2 Delivered on the web to use XML applications and content. It combines tools created by relational databases, multimedia and XML content. StoryServer is a web content application platform for establishing, management, and Deliver service-based web applications, such as online publishing, knowledge management, and e-commerce systems. (Note: CNET has financial interest in Vignette.) XPublish: XPublish is an XML publishing system for Web site development and management, The developer is allowed to make in XML, or use the XML component to extend the current HTML document, and then release the site in html to allow any standard web browser to access. It contains a cascading style sheets editor. WebMethods: The company produces XML-based Web Automation software, providing fast integration and direct access to commercial applications and web data. Its Web Interface Definition Language (WIDL) will automate all interactions with HTML / XML and tables to provide on standard Web protocols Performance requirements - a general method for answering interaction mode. Of course, if XML is everywhere on the web, you can see almost every web-based application, especially HTML editor, database software, and e-commerce software, will Quickly join the support for each level of XML. <<