Usage of XML Parser: Learn to Apply All of the Parsers

For the data to be successfully transferred from one system to another, it has to be put into a universal format that each of them could easily read and understand.

The XML format is used for this purpose of making data understandable. Meaning eXtensible Markup Language, XML is a language used to encode documents, so they are simple and easy to use across the Internet.

XML documents frequently contain information that developers need to retrieve in a usable form. To do that, they apply a selected XML parser. This software will read the XML file and retrieve data according to the structure. Without parsing, you could not create, read and edit XML files via your script.

XML Parser: Main Tips

• XML is a language for structuring data, so you can readily share it across websites.
• Good examples of XML web technologies include podcasts, RSS feeds, etc.
• XML syntax is very similar to HTML, except that you create tags yourself.
• A PHP XML parser is a program or extension, allowing you to edit XML files by turning them into data forms that you can read, iterate through, otherwise manipulate and access via PHP codes.
• They are divided into two main types: tree-based and event-based parsers.

Tree-Based Parsers Explained

This type of PHP XML parser holds the whole XML file in its memory, transforms it into what we call a tree structure, and then lets the web application navigate it. As soon as the document undergoes XML parsing process, you can access all the elements at once.

Due to its nature of holding the whole document in its memory, tree-based parsers are excellent for smaller XML files. Unfortunately, it starts to affect performance when handling bigger ones negatively.

These two are some of the more popular tree-based XML parsers:

• SimpleXML
• DOM

Meaning of Event-Based Parsers

Instead of having PHP parse XML file by having it all in its memory and reading multiple nodes at once, an event-based parser reads a single node whenever it is required. Upon moving to another node, the old one is discarded.

Due to its nature of only accessing parts of an XML document that are required, parsers of this type are generally more lightweight (use up less memory and less code). Therefore, these parsers are a better choice for XML parsing bigger documents.

These two are some of the more popular event-based XML parsers:

• XMLReader
• Expat

XML Parser: Summary

• XML language is used to structure data and has a similar syntax to HTML. Data in this format can be easily shared across websites, so this technology is often used for RSS feeds, podcasts and similar things.
• To turn XML files into accesable and readable data, you need an XML parser. It might be an extension or an independent program that lets PHP parse XML documents.
• In PHP XML parsers are divided into two groups: event-based (better for huge documents) and tree-based (better for smaller documents).