Should XML use tabs or spaces?
XML files Eclipse configuration
Eclipse should be configured to use spaces (not tabs) and an indentation of 2 spaces is used for XML-like code. Line width is 120.
Does indentation matter in XML files?
Indenting XML tags is never required for parsing. However, the point of XML is to be human as well as machine readable, so indentation is generally worth having, as it makes it far easier for human readers to work with and take in the structure at a glance. It's not completely ignored.
How to format XML document?
Use the Formatting options page to specify how elements and attributes are formatted in your XML documents. To access XML formatting options, choose Tools > Options > Text Editor > XML, and then choose Formatting.