XLink and XPointer Tutorial

XLink and XPointer Tutorial
XLink

Linking in XML is divided into two parts: XLink and XPointer.

XLink defines a standard way of creating hyperlinks in XML documents.

XPointer allows the hyperlinks to point to more specific parts (fragments) in the XML document.

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Table of Contents

XLink and XPointer Introduction
This chapter explaines what the XLink and XPointer languages are.

XLink and XPointer Syntax
The syntax of XLink and XPointer.

XLink Example
An example of using XLink in an XML document.

XPointer Example
An example of using XLink and XPointer in an XML document.

XLink Summary
This chapter contains a summary on what you have learned in this tutorial and a recommendation on what subject you should study next.

XLink Reference
XLink attribute reference.

Multimedia Tutorial

Multimedia Tutorial
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In this Multimedia tutorial you will learn how to add multimedia (sound and video) to your web pages.

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Table of Contents

Introduction to Multimedia
This chapter describes what multimedia is and how multimedia can be handled by web browsers.

Sound Formats
This chapter describes the most common - or popular - sound formats.

Video Formats
This chapter describes the most common - or popular - video formats.

Browser Sounds
This chapter describes how to play sounds from a web page.

Browser Videos
This chapter describes how to play videos from a web page.

Windows Media Formats
This chapter describes the new Windows Media formats.

Object Intro
This chapter describes the object element.

Object QuickTime
This chapter describes how to play QuickTime movies with the object element.

Object RealMedia
This chapter describes how to play Real Audio and Real Video with the object element.

Tag Reference
The HTML multimedia tag reference.

Player Reference
The Windows Media Player reference.

SQL Tutorial

SQL is a standard computer language for accessing and manipulating databases.

In this tutorial you will learn how to use SQL to access and manipulate data in Oracle, Sybase, SQL Server, DB2, Access, and other database systems.

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SQL Quiz Test

Test your SQL skills at W3Schools!

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Exam - Get Your Diploma!

W3Schools' Online Certification Program is the perfect solution for busy professionals who need to balance work, family, and career building.

The ASP Developer Certificate is for developers who want to document their knowledge of ASP, SQL, and ADO.

JavaScript

JavaScript Operators
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The operator = is used to assign values.

The operator + is used to add values.

The assignment operator = is used to assign values to JavaScript variables.

The arithmetic operator + is used to add values together.

y=5;
z=2;
x=y+z;

The value of x, after the execution of the statements above is 7.
JavaScript Arithmetic Operators

Arithmetic operators are used to perform arithmetic between variables and/or values.

Given that y=5, the table below explains the arithmetic operators:
Operator Description Example Result
+ Addition x=y+2 x=7
- Subtraction x=y-2 x=3
* Multiplication x=y*2 x=10
/ Division x=y/2 x=2.5
% Modulus (division remainder) x=y%2 x=1
++ Increment x=y++ x=6
-- Decrement x=y-- x=4

JavaScript Assignment Operators

Assignment operators are used to assign values to JavaScript variables.

Given that x=10 and y=5, the table below explains the assignment operators:
Operator Example Same As Result
= x=y x=5
+= x+=y x=x+y x=15
-= x-=y x=x-y x=5
*= x*=y x=x*y x=50
/= x/=y x=x/y x=2
%= x%=y x=x%y x=0

The + Operator Used on Strings

The + operator can also be used to add string variables or text values together.

To add two or more string variables together, use the + operator.

txt1="What a very";
txt2="nice day";
txt3=txt1+txt2;

After the execution of the statements above, the variable txt3 contains "What a verynice day".

To add a space between the two strings, insert a space into one of the strings:

txt1="What a very ";
txt2="nice day";
txt3=txt1+txt2;

or insert a space into the expression:

txt1="What a very";
txt2="nice day";
txt3=txt1+" "+txt2;The +

After the execution of the statements above, the variable txt3 contains:

"What a very nice day"
Adding Strings and Numbers

Look at these examples:

x=5+5;
document.write(x);

x="5"+"5";
document.write(x);

x=5+"5";
document.write(x);

x="5"+5;
document.write(x);

Try it yourself.

The rule is:

If you add a number and a string, the result will be a string.

Nanotechnology

Abstract:
Marc Silverman is resigning as director of CTEK's Boulder Venture Center to start a new seed-stage funding group called Mountain Angel Capital, or MAC.

Silverman, a founder and former chief executive of Performance Health Technologies, took over the CTEK position in late May, replacing Jim Pollock, who left to head up a startup in Golden.

Mountain Angel Capital, Silverman said, primarily wants to invest in nanotechnology, software, clean tech and medical devices. It will announce relationships with a local venture capital company, an investment bank and a group of individual investors, all former CEOs who have run their own companies.

The new group plans to incorporate in January, and will make further announcements then.

XML Files

Viewing XML Files

In Firefox and Internet Explorer:

Open the XML file (typically by clicking on a link) - The XML document will be displayed with color-coded root and child elements. A plus (+) or minus sign (-) to the left of the elements can be clicked to expand or collapse the element structure. To view the raw XML source (without the + and - signs), select "View Page Source" or "View Source" from the browser menu.

In Netscape 6:

Open the XML file, then right-click in XML file and select "View Page Source". The XML document will then be displayed with color-coded root and child elements.

In Opera 7 and 8:

In Opera 7: Open the XML file, then right-click in XML file and select "Frame" / "View Source". The XML document will be displayed as plain text. In Opera 8: Open the XML file, then right-click in XML file and select "Source". The XML document will be displayed as plain text.

Viewing XML Files

View a simple XML file (note.xml)
View the same XML file with an error
View an XML CD catalog
View an XML plant catalog
View an XML food menu

Viewing XML files with a dtd

View note.xml with an internal dtd
View note.xml with an external dtd

The Microsoft XML parser

View a simple XML file (xml_note.xml)
Loading the same file into the parser
Traversing the node tree of the file
Loading the same file into HTML

Displaying using JavaScript

View a simple XML file (xml_note.xml)
Format the same file with JavaScript

XML and CSS

View an XML CD catalog
View the corresponding CSS file
Display the CD catalog formatted with the CSS file

XML and XSL

View an XML food menu
View the corresponding XSL stylesheet
Display the food menu styled with the XSL stylesheet (IE6)
Display the food menu styled with the XSL stylesheet (IE5)

Data Binding

View an XML CD catalog
Bind the CD catalog to an HTML table
Add , , elements

Database Output

View XML output from a database

Displayed as HTML

View an XML CD catalog
See how the CD catalog can be displayed inside HTML elements
See how the CD catalog can be displayed inside an HTML table
See how to navigate the CD catalog
A simple CD catalog application

Requesting XML data from a server

Send a request to the server
Communicating with a server using XML

Using the XMLHttpRequest Object

Load an XML file with XML HTTP (JavaScript)
Load an XML file with XML HTTP (VBScript)
Load a textfile into a div element with XML HTTP (JavaScript)
Make a HEAD request with XML HTTP (JavaScript)
Make a specified HEAD request with XML HTTP (JavaScript)

XML Behaviors

XML Behaviors

Web design

Users Are Scanners

If you think a typical user will read the entire content of your Web pages, you are wrong.

No matter how much useful information you put into a Web page, a visitor will only spend a few seconds scanning it before they decide whether to leave it or to stay.

If you want a visitor to read your text, be sure to make your point in the very first sentence of the page. After that you should try to keep them occupied with short paragraphs and interesting new headers all the way down the page.
Less Is More

Try to keep all sentences as short as possible. Try to keep your paragraphs as short as possible. Try to keep your chapters as short as possible. Try to keep your pages as short as possible.

Use a lot of space between your paragraphs and chapters. Pages overloaded with text will kill your audience.

Don't place too much content on a single page. If you have a lot to say, try to break your information into smaller chunks and place it on different pages. Don't expect any visitor to scroll all the way down to the bottom of a page with thousands of words.
Navigation

Try to create a navigation structure that is common for all the pages in your Web.

Keep the use of hyperlinks inside your text paragraphs to a minimum. Don't use hyperlinks inside text paragraphs to send your visitors to every random page of your Web. That will destroy the feeling of a consistent navigation structure.

If you must use hyperlinks, add them to the bottom of a paragraph or to the navigation menus of your site.
Download Speed

A common mistake made by many web designers is to develop a site on a local machine with direct access to the data, or to develop the site over a high-speed Internet connection. Sometimes developers are not aware of the fact that some of their pages take a long time to download.

Internet usability studies tell us that most visitors will leave a Web page that takes more than 7 seconds to download.

Before you publish any content heavy pages, make sure they are tested over a low-speed modem connection. If your pages take a long time to download, you might consider removing some of your graphic or multimedia content.
Let Your Audience Speak!

Feedback from your users is a very good thing. Your visitors are your "customers". Very often they will give you some valuable wisdom, or advise you, completely free of charge, about what you could have done better.

If you provide a simple way to reach you, you will get a lot of positive input from a lot of people with different skills and knowledge.