oga/doc/manually_creating_documents.md

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# Manually Creating Documents
Besides being able to parse documents, Oga also allows you to create documents
manually. This can be useful if you want to dynamically generate XML/HTML.
Documents can be greated in two ways:
1. Full blown documents (using {Oga::XML::Document})
2. XML fragments (using just {Oga::XML::Element} and the likes)
For example, lets create a document with a specific encoding and a single
element:
xml_decl = Oga::XML::XmlDeclaration.new(:encoding => 'UTF-16')
document = Oga::XML::Document.new(:xml_declaration => xml_decl)
element = Oga::XML::Element.new(:name => 'example')
document.children << element
If you now serialize this back to XML (by calling `document.to_xml`) you'd get
the following XML:
<?xml version="1.0" encoding="UTF-16" ?>
<example />
You can also serialize elements on their own:
element.to_xml
This would output:
<example />
## Adding/Removing Attributes
The easiest way to add (or remove) attributes is by using {Oga::XML::Element#set}
and {Oga::XML::Element#unset}. For example, to add an attribute:
element = Oga::XML::Element.new(:name => 'example')
element.set('class', 'foo')
element.to_xml # => "<example class=\"foo\" />"
And to remove an attribute:
element.unset('class')
## Modifying Text
Modifying text of elements can be done in two ways:
1. Adding {Oga::XML::Text} instances to the list of child nodes of an
{Oga::XML::Element} instance
2. Using {Oga::XML::Element#inner\_text=}
The second option is the easiest and recommended way of doing this. Usage is
quite simple:
element = Oga::XML::Element.new(:name => 'p')
element.inner_text = 'Hello'
element.to_xml => "<p>Hello</p>"
Special characters such as `&` and `<` are escaped automatically when calling
{Oga::XML::Element#to_xml}.