Lua

Compress XML Tree

See more XML Examples

Demonstrates how to compress and restore the entire subtree rooted at an XML node.

The input XML, available at http://www.chilkatsoft.com/data/compress2.xml, is this:

<root>
    <lazydog>
        <fox>The quick brown fox jumps over the lazy dog</fox>
    </lazydog>
    <fox>The quick brown fox jumps over the lazy dog</fox>
    <child>
        <grandchild>The quick brown fox jumps over the lazy dog</grandchild>
    </child>
    <child>
        <grandchild>The quick brown fox jumps over the lazy dog</grandchild>
    </child>
</root>

Lua

local chilkat = require("chilkat")

local xml = chilkat.Xml.new()

-- The sample input XML is available at http://www.chilkatsoft.com/data/compress2.xml
local success = xml:load_xml_file("compress2.xml")
if not success then
    print(xml.last_error_text)
    return
end

-- Zip compress the root node's entire subtree:
success = xml:zip_tree()

-- Examine the new XML document:
print(xml:get_xml())

-- This is the XML w/ the compressed subtree in Base64 encoded format:

-- <root><![CDATA[4+WyKcrPL7Hj5VIAApucxKrKlPx0KBcslJZfYReSkapQWJqZnK2QVJRfnqcAFFPIKs0tKFbIL0st
-- UigBSoN0KgC12uiDNECN00c1jyKzkjMyc1KQHZZelJiXAhElyUwkfTBnovDoYZGNPjTUAQ==
-- ]]></root>

-- Now uncompress and show that the original subtree was restored:
success = xml:unzip_tree()
print(xml:get_xml())