Understanding XML View & 5 ways That The Present Version Is Different

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XML is an extensible markup programming language. It uses tags which form a text-based format, used to represent any structured information. It follows a certain set of rules for encoding documents, making them both human and machine-readable. On its own, XML cannot describe data in a markup-structured manner. It uses markup tags defined by its standard, and by the user.

Designed in 1996, XML focus was to meet all the challenges of publishing large-scale electronics. It has seen many changes and revisions that adapt well to current technology market requirements. Today, hundreds of extended XML formats use XML as their base specification in rendering information in their publications. XML has gone a step further to act as an information interchange for integration standards, permitting data storage to get more use and more prevalence.

Why Use XML

Designed to carry data, the application of XML is wholly dependent on the application of data, as well as the implementation process. It gives many benefits, such as:

  • XML carries data and does not do anything else, making simplicity a benefit.
  • Users can define all tags fit for the purpose at hand since XML is an extensible language. This makes it very flexible.
  • The plain data format allows both humans and machines to read it easily. XML has the capability of self-describing itself, if allowed to do so by the extended XML format.
  • XML Syntax Rules are logical and extremely simple. The rules are easy to use, and easy to learn even for beginners. Furthermore, if the task of using XML syntax rules proves difficult, there is help readily available. You can hire XML experts from freelancer.com.

How XML Works

-Every XML document must have a root element, which acts as the parent of all the other elements in the document

< root >

<child >

< subchild > ..... < /subchild >

</child >

< /root >

In the example given here, the root element is <note>

< ?XML version ="1.0"

encoding ="UTF-8 "? >

< note >

<to > Tove< /to >

<from > Jani </from >

<heading > Reminder < /heading >

<body > Do not forget me this

weekend! </body >

< /note >

-This line, called the XML prologue, is optional and if it exists in any document it must come first

< ?XML version ="1.0"

encoding ="UTF-8 "? >

-Note that some XML documents contain international characters.

Below is a good example:

Norwegian or French

Avoid errors by specifying what encoding you used, or simply save your files as UTF-8, which is the default character used in encoding XML documents. It is also the default encoding for many other programming languages such as JavaScript, CSS, html5, SQL, and PHP.

-Your XML elements must always have closing tags

Some of the elements may work well without a closing tab, while others will not. However, it is illegal to omit that closing tag. Below are few examples:

< p >this is the story.

< br >

< p >this is the story. < /p >

< br / >

The above XML prolog does not have a closing tag, which is okay because the prolog is not a part of the document.

XML Tags are Case Sensitive and the tag <Letter> is different from the tag <letter>.

Always write the opening and closing tags with a similar case.

< Message >This is incorrect< /message >

< Message >this is correct </message >

“Start and end tags” are also referred to as "Opening and closing tags", and either is allowed.

-Nest all XML elements properly

Improperly nested XML elements look like this:

< b >< i > bold and italic text</

b >< /i >

Properly nested XML elements look like this

< b >< i > bold and italic text</

i >< /b >

The example shown above, "Properly nested" means that the <i> element is opened inside the <b> element and closed inside the <b> element.

-Quote XML Attribute Values

Just like in html, XML elements have name/value pair attributes.

It is necessary to have Attribute values quoted in XML always.

INCORRECT quote:

< note date =12/11/2007>

<to > Tove< /to >

<from > Jani </from >

< /note >

CORRECT quote:

< note date ="12/11/2007">

<to > Tove< /to >

<from > Jani </from >

< /note >

In the first document, there is no quoting of the date attribute while in the second, there is a quote of the attribute.

-References entity

Different characters have special different meanings in XML.

A character like "<" placed inside an XML element generates, because it is interpreted as the start of a new element which actually is an error.

<message>salary < 1000</message>ing replace the "<" character with an entity reference, clears the error. < message >salary &lt; 1000< /message >

The five pre-defined entity references in XML are:

&lt; < less than

&gt; > greater than

&amp; & ampersand

&apos; ' apostrophe

&quot; quotation mark

< and & are illegal in XML, but become valid when replaced with > with &gt;

-Comments XML

Writing comments in XML and HTML are very similar.

<!-put comment here -->

Avoid putting two dashes in the middle of a comment like the example below:

<!-put a - comment here -->

However, as strange as it may look, the example below is okay to use.

<!-put a - - comment here -->

-Preserved White-space in XML

There are no truncating multiple white spaces in XML. However, in html, it is possible to truncate several.

Five Ways XML Got Better

For developers using XML editor, test view remains popular for editing purposes. This makes doing the job easy, through the efficient use of spy text and other additional functions.

Some of the new functionalities that make XML better than before are:

Better and more convenient help for XML validation

The patent included in XML spy provides detailed information of every validation error that comes up, and gives a variety of options for fixing the errors automatically on a single click.

XML spy also indicates the smart fix opportunities, and validation errors in the text margin situated next to the code. It shows all this information in the text view window.

By a click of the mouse on the error, the indicator reads the smart fix light bulb and the validation error, giving suggestions on how to fix and implement them as applied by XML spy.

This feature proves useful when working through several validation errors at once, as it is easier to identify and tackle each one at a time. Considered revolutionary, smart fix still remains the most convenient troubleshooting method.

Searching using multi-line

The new, find/replace dialog modernized XML  introduced in 2017 in XMLSpy 2017 has the ability to support searches that are multi-line driven. The functionality found in the XML editor was supported by carrying out searches through expressions. Now, it uses regex to replace and find XML data with several multiple lines.

Syntax Coloring

One of the many advantages of using a text-based XML editor is syntax coloring. XPath expressions used in stylesheets now hold the same coloring as the one used in XPath Builder and Tester.

When you set apart the XPath, the editing of new documents and the existing code becomes easier to understand.

XQuery debugging and XSLT

The powerful oxygen XSLT debugger using Saxon and Xalan transformation engines detects bugs in the stylesheet. In the debugging perspective, the XPath dynamic evaluation steps into XPath expression and templates, cleaning up everything.

Variables view of XSLT

Variables view has been updated, when all XSLT variables and parameters visible in the XSLT context are debugged. The processor changes the whole context to make it easier, thus offering the actual scope and value.

Conclusion

XML is only getting better, and still has a long way to go. Developers come up with new updates every other year, and in the future we expect nothing but a very advanced XML TextView. Since XML is one of the most widely-used  programming languages, especially by Microsoft Excel users, these updates are a great relief.

Have you learned anything from the above article? Do you have any questions or comments to make? Kindly reach us via the comment box below - and don’t forget to share this article!

 

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Gönderildi 27 Eylül, 2017

LucyKarinsky

Software Developer

Lucy is the Development & Programming Correspondent for Freelancer.com. She is currently based in Sydney.

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