A Beginner's Guide to Reading and Editing XML Files

Last Updated: 25 Mar, 2025

Why Learn XML Editing?

XML (Extensible Markup Language) is widely used for storing and transporting data in software applications, web services, and configuration files. However, many people struggle to open or modify XML files properly. This guide will help beginners and developers learn how to read, edit, validate, and format XML efficiently.

Tools to Open XML Files

1. Notepad (Windows Built-in Editor)

• Right-click the XML file and select Open with > Notepad.
• Suitable for quick edits but lacks syntax highlighting.

2. Visual Studio Code (VS Code)

• Free, lightweight, and feature-rich code editor.
• Provides syntax highlighting, auto-formatting, and extensions for XML validation.

3. Microsoft Excel

• Can open XML as a structured table.
• Navigate to File > Open > Browse, select the XML file, and choose As an XML table.

4. Online XML Editors

• Websites like CodeBeautify, XMLGrid, and XMLViewer allow XML viewing and editing without installing software.
• Useful for quick checks and formatting.

Editing XML: Syntax Rules and Best Practices

1. Follow Proper Tag Structure

   • Every opening tag must have a matching closing tag.

   <person>
       <name>John Doe</name>
   </person>
   

2. Use Meaningful Tag Names

   • Avoid generic tags like <item> or <data> unless necessary.

3. Ensure Proper Nesting

   • Incorrect:

   <parent>
       <child1>
       <child2></child2>
       </child1>
   </parent>
   

   • Correct:

   <parent>
       <child1>
           <child2></child2>
       </child1>
   </parent>
   

4. Escape Special Characters

   • Use < for <, > for >, & for &.

Validating XML with XSD (XML Schema Definition)

XML validation ensures data integrity by defining rules with an XSD file.

Steps to Validate XML:

1. Create an XSD File (Defines XML structure)

   <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
       <xs:element name="person">
           <xs:complexType>
               <xs:sequence>
                   <xs:element name="name" type="xs:string"/>
               </xs:sequence>
           </xs:complexType>
       </xs:element>
   </xs:schema>
   

2. Link XML to XSD

   <person xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:noNamespaceSchemaLocation="person.xsd">
       <name>John Doe</name>
   </person>
   

3. Validate Using Tools

   • VS Code Extensions: Install “XML Tools” extension.
   • Online Validators: Websites like XMLValidation.com.

How to Pretty-Print or Format XML

Unformatted XML is hard to read. Use these methods to format XML:

1. VS Code: Right-click and select “Format Document” or use Shift + Alt + F.
2. Notepad++: Install “XML Tools” plugin and use “Pretty Print (XML only)”.
3. Online Formatters: Use tools like CodeBeautify or XML Formatter.
4. Python (For Developers):

   import xml.dom.minidom
   xml_str = """<person><name>John</name></person>"""
   dom = xml.dom.minidom.parseString(xml_str)
   pretty_xml = dom.toprettyxml()
   print(pretty_xml)
   

Conclusion

XML is essential for data storage and transfer, and knowing how to read and edit it effectively is crucial. By using the right tools, following best practices, validating with XSD, and formatting properly, you can efficiently work with XML files in any application.