411 REFERENCE · Wikibooks
XQuery/Web XML Viewer
Reference material by Wikibooks contributors. This retains its source identity and is not 411 news reporting.
Motivation
You want to view XML documents using your web browser using HTML markup.
Method
We will use an XQuery function that uses the dispatch pattern and the typeswitch function.
Sample Input
<aaa a1="A1" a2="A2" a3="A3">
<bbb b1="B1" b2="B2" b3="B3">BBB</bbb>
<ccc c1="C1" c2="C2" c3="C3">
<ddd d1="D1" d2="D2" d3="D3">DDD</ddd>
<eee>
<fff>FFF</fff>
</eee>
</ccc>
</aaa>
Sample XML to HMTL Function
(: sequence dispatcher :)
declare function xml-to-html:dispatch($input as node()*, $depth as xs:integer) as item()* {
let $left-margin := concat('margin-left: ', ($depth * 5), 'px' )
for $node in $input
return
typeswitch($node)
case text() return normalize-space(<span class="d">{$node}</span>)
case element()
return
<div class="element" style="{$left-margin}">
<span class="t"><{name($node)}</span>
{ (: for each attribute create two spans for the name and value :)
for $att in $node/@*
return
(
<span class="an"> {name($att)}=</span>,
<span class="av">"{string($att)}"</span>
)
}
{normalize-space(<span class="t">></span>)}
{ (: now get the sub elements :)
for $c in $node
return xml-to-html:dispatch($c/node(), $depth + 1)
}
<span class="t"></{name($node)}></span>
</div>
(: otherwise pass it through. Used for comments, and PIs :)
default return $node
};
Sample Driver
xquery version "1.0";
import module namespace xml-to-html="http://example.com/xml-to-html" at "xml-to-html.xqm";
let $title := 'View XML as HTML'
let $input :=
<aaa a1="A1" a2="A2" a3="A3">
<bbb b1="B1" b2="B2" b3="B3">BBB</bbb>
<ccc c1="C1" c2="C2" c3="C3">
<ddd d1="D1" d2="D2" d3="D3">DDD</ddd>
<eee>
<fff>FFF</fff>
</eee>
</ccc>
</aaa>
let $output := xml-to-html:xml-to-html($input, 1)
return
<html>
<head>
<title>{$title}</title>
<link type="text/css" rel="stylesheet" href="syntax-colors-oxygen.css"/>
</head>
<body>
<div class="xml">
{$output}
</div>
</body>
</html>
Sample Output
<div class="xml">
<div class="element" style="margin-left: 5px">
<span class="t"><aaa</span>
<span class="an">a1=</span>
<span class="av">"A1"</span>
<span class="an">a2=</span>
<span class="av">"A2"</span>
<span class="an">a3=</span>
<span class="av">"A3"</span>><div class="element" style="margin-left: 10px">
<span class="t"><bbb</span>
<span class="an">b1=</span>
<span class="av">"B1"</span>
<span class="an">b2=</span>
<span class="av">"B2"</span>
<span class="an">b3=</span>
<span class="av">"B3"</span>>BBB<span class="t"></bbb></span>
</div>
<div class="element" style="margin-left: 10px">
<span class="t"><ccc</span>
<span class="an">c1=</span>
<span class="av">"C1"</span>
<span class="an">c2=</span>
<span class="av">"C2"</span>
<span class="an">c3=</span>
<span class="av">"C3"</span>><div class="element" style="margin-left: 15px">
<span class="t"><ddd</span>
<span class="an">d1=</span>
<span class="av">"D1"</span>
<span class="an">d2=</span>
<span class="av">"D2"</span>
<span class="an">d3=</span>
<span class="av">"D3"</span>>DDD<span class="t"></ddd></span>
</div>
<div class="element" style="margin-left: 15px">
<span class="t"><eee</span>><div class="element" style="margin-left: 20px">
<span class="t"><fff</span>>FFF<span class="t"></fff></span>
</div>
<span class="t"></eee></span>
</div>
<span class="t"></ccc></span>
</div>
<span class="t"></aaa></span>
</div>
</div>
Sample CSS File
File: syntax-colors-oxygen.css
/* Begin and end tag Delimiter */
.t {color: blue;}
/* Attribute Name and equal sign */
.an {color: orange;}
/* Attribute Values and equal sign */
.av {color: orange;}
/* Element Data Content */
.d {color: black;}
Screen Image
screen image of rendering in browser with CSS file