Belgian Waffles $ Two of our famous ."/>
About the Tutorial. XML stands for Extensible Markup Language and is a text- based markup language derived from Standard Generalized Markup Language. XML Tutorial in PDF - Learn XML in simple and easy steps starting from basic to advanced concepts with examples including Overview, XML document syntax. xml version="" encoding="UTF-8"?> Belgian Waffles $ Two of our famous .
|Language:||English, Spanish, Dutch|
|Genre:||Academic & Education|
|Distribution:||Free* [*Register to download]|
XML, which stands for Extensible Markup Language, was defined by the. XML Working .. As you'll learn, you can write an XML document to conform to either. XML, the Extensible Markup Language, has been hailed as a technical revolution This tutorial cuts through the hype to show you what XML is all about. XML is. If you want to study these subjects first, find the tutorials on our Home page. HTML is about displaying information, while XML is about carrying information.
Instead, Internet Explorer displays messages about the beginning and end tags not matching. Here are a few things to note about your naming:.
An XML document can have some empty tags that do not have anything inside and can be expressed as a single tag instead of as a set of beginning and end tags.
Nesting is the placement of elements inside other elements. These new elements are called child elements, and the elements that enclose them are their parent elements. Nesting can be many levels deep in an XML document. A common syntax error is improper nesting of parent and child elements. Any child element must be completely enclosed between the starting and end tags of its parent element.
Sibling elements must each end before the next sibling begins. The code in Listing 3 shows proper nesting. The tags begin and end without intermingling with other tags. Attributes are sometimes added to elements.
Attributes consist of a name-value pair, with the value in double quotation marks " , thus: Attributes provide a way to store additional information each time you use an element, varying the attribute value as needed from one instance of an element to another within the same document. You type the attribute—or even multiple attributes—within the starting tag of an element: If you add multiple attributes, separate them with spaces: Listing 4 shows the XML file as it currently stands.
You can use as few or as many attributes as you feel you need. Consider the details you might add to your documents. Attributes are especially helpful if documents will be sorted—for example, by type of recipe. Attribute names can include the same characters as element names, with similar rules for omitting spaces and starting names with alphabetic characters.
If you follow the rules outlined in your structure, you can easily produce well-formed XML. But consider the aforementioned example of sorting by recipe type. Validation is checking your document's structure against rules for your elements and how you defined child elements for each parent element.
This line refers to the DTD or schema your list of elements and rules to be used to validate that document.
This example assumes that your element list file is named filename. Entities can be phrases of text or special characters.
They can point internally or externally. Entities must be declared and expressed properly to avoid errors and to ensure proper display. You cannot typed special characters directly into your content. To use a symbol in your text, you must set it up as an entity using its character code. You can set up phrases such as a company name as an entity, then type the entity throughout your content.
This code identifies the text that stands in for the entity.
Using entities might help you avoid typing the same phrase or information repeatedly. It can also make it easier to adjust the text—perhaps if the company name changes—in many places with a simple adjustment in the entity definition. If it displays your elements, attributes, and content, then the XML is well formed. If instead errors are displayed, you likely have a syntax error and need to review your document carefully for typos or missing tags and punctuation.
As mentioned in Nest the elements , an element that contains another element is the parent of that contained element. Remember to nest your sibling elements properly, as well. Listing 7 shows well-formed and properly nested XML. The line breaks make it easier for you to read your code and do not affect the XML.
You might wish to experiment with your test files, and move the end tags and beginning tags, to become familiar with the resulting error messages.
XML is designed as an easy-to-use and easy-to-extend markup language. With XML, you can create your own elements, giving you the freedom to precisely represent your pieces of information. Rather than treating your documents as headings and paragraphs, you can identify each part within the document.
For efficiency, you'll want to define a finite list of your elements and stick to them. As you start out and get used to XML, feel free to experiment with element names as you build practice files.
You place much of your content in elements by surrounding your content with tags. For example, suppose you need to create an XML cookbook.
To mark up the recipe name, you enclose that text in your element by placing the beginning tag before your text and the ending tag after your text. You might call the element recipename.
Then, type your text Ice Cream Sundae. These tags form an element, into which you can enter content or even other elements. You can create element names for individual documents or for document sets. You can craft the rules for how the elements fit together based on your specific needs. You can be very specific or keep element names more generic. You can create rules for what each element is allowed to contain and make these rules strict, lax, or something in between.
Just be sure to create elements that identify the parts of your documents that you feel are important. Because this declaration must be first in the file, if you plan to combine smaller XML files into a larger file, you might want to omit this optional information. Create your root element The root element's beginning and end tags surround your XML document's content.
Only one root element is in the file, and you need this "wrapper" to contain it all. See Download for the full XML file. Listing 1.
Name your elements Matching case in tags When you create your XML, be sure that your beginning and end tags match in case. If the case doesn't match, you might get an error when you use or view the XML. Internet Explorer, for example, will not display the file content if the case is mismatched.
Instead, Internet Explorer displays messages about the beginning and end tags not matching. Here are a few things to note about your naming: Spaces are not allowed in the element names. Names must begin with an alphabetic character, not a number or symbol.
After this first character, you can use any combination of letters, numbers and the allowed symbols. Case does not matter, but be consistent to avoid confusion. Listing 2. Nest the elements Nesting is the placement of elements inside other elements. These new elements are called child elements, and the elements that enclose them are their parent elements. Nesting can be many levels deep in an XML document. A common syntax error is improper nesting of parent and child elements.
Any child element must be completely enclosed between the starting and end tags of its parent element. Sibling elements must each end before the next sibling begins.
The code in Listing 3 shows proper nesting. The tags begin and end without intermingling with other tags. Listing 3.