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javascript to format/pretty-print XML
Raw
formatXML.js
The MIT License (MIT)
Copyright (c) 2016 Stuart Powers
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
function formatXml(xml) {
var formatted = '';
var reg = /(>)(<)(\/*)/g;
xml = xml.replace(reg, '$1\r\n$2$3');
var pad = 0;
jQuery.each(xml.split('\r\n'), function(index, node) {
var indent = 0;
if (node.match( /.+<\/\w[^>]*>$/ )) {
indent = 0;
} else if (node.match( /^<\/\w/ )) {
if (pad != 0) {
pad -= 1;
}
} else if (node.match( /^<\w([^>]*[^\/])?>.*$/ )) {
indent = 1;
} else {
indent = 0;
}
var padding = '';
for (var i = 0; i < pad; i++) {
padding += ' ';
}
formatted += padding + node + '\r\n';
pad += indent;
});
return formatted;
}
xml_raw = '<foo><bar><baz>blahblah</baz><baz>tralala</baz></bar></foo>';
xml_formatted = formatXml(xml_raw);
xml_escaped = xml_formatted.replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;').replace(/ /g, '&nbsp;').replace(/\n/g,'<br />');
var mydiv = document.createElement('div');
mydiv.innerHTML = xml_escaped;
document.body.appendChild(mydiv);
Raw
javascript_xml_pretty_print.html
<html>
<head>
<title>Javascript xml pretty print - Stuart Powers</title>
<script src="http://bit.ly/jqymin"></script>
<style>
textarea {
width: 80%;
height: 50%;
overflow-x: scroll;
overflow-y: scroll;
display: block;
border: 1px solid black;
padding: 5px;
margin: 5px;
}
</style>
<script>
function formatXml(xml) {
var formatted = '';
var reg = /(>)(<)(\/*)/g;
xml = xml.replace(reg, '$1\r\n$2$3');
var pad = 0;
jQuery.each(xml.split('\r\n'), function(index, node)
{
var indent = 0;
if (node.match( /.+<\/\w[^>]*>$/ ))
{
indent = 0;
}
else if (node.match( /^<\/\w/ ))
{
if (pad != 0)
{
pad -= 1;
}
}
else if (node.match( /^<\w[^>]*[^\/]>.*$/ ))
{
indent = 1;
}
else
{
indent = 0;
}
var padding = '';
for (var i = 0; i < pad; i++)
{
padding += ' ';
}
formatted += padding + node + '\r\n';
pad += indent;
});
return formatted;
}
$(function(){
var url = "http://careers.stackoverflow.com/jobs/feed?searchTerm=python&location=02144&range=30";
$.ajax({
url: url,
dataType:"text",
beforeSend:function(){$('.info').append($('<p>requesting: '+url+'</p>'));},
error:function(){$('.info').append($('<p>error! '+url+'</p>'));},
success: function(data) {
$('.unformatted').text(data);
}
});
$.ajax({
url: url,
dataType:"text",
beforeSend:function(){
$('.info2').append($('<p>requesting '+url+'</p>'));
$('.info2').append($('<p>and formatting the response!'));
},
error:function(){$('.info2').append($('<p>error! '+url+'</p>'));},
success: function(data) {
xml_neat = formatXml(data);
$('.formatted').text(xml_neat);
}
});
});
</script>
</head>
<body>
<code>
Also available <a href="http://sente.cc/misc/javascript_xml_pretty_print.html">
http://sente.cc/misc/javascript_xml_pretty_print.html
</a>
</code>
<pre class="info"></pre>
<h3>unformatted</h3>
<textarea class="unformatted"></textarea>
<h3>formatted</h3>
<textarea class="formatted"></textarea>
<body>
</html>
@vishumertiya
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Thank u so much .. It helps a lot

@edemaine
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@Risord Indeed, that regular expression should be /^<\w([^>]*[^\/])?>.*$/

@sente
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Author

sente commented Dec 16, 2016

@edemaine, @Risord -- thank you. I've updated the regular expression.

@grubersjoe
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grubersjoe commented Nov 10, 2017 •
edited
Loading

Thanks for the code.

Here's an adapted ES6 variant:

formatXml(xml) {
    const PADDING = ' '.repeat(2); // set desired indent size here
    const reg = /(>)(<)(\/*)/g;
    let pad = 0;

    xml = xml.replace(reg, '$1\r\n$2$3');

    return xml.split('\r\n').map((node, index) => {
        let indent = 0;
        if (node.match(/.+<\/\w[^>]*>$/)) {
            indent = 0;
        } else if (node.match(/^<\/\w/) && pad > 0) {
            pad -= 1;
        } else if (node.match(/^<\w[^>]*[^\/]>.*$/)) {
            indent = 1;
        } else {
            indent = 0;
        }

        pad += indent;

        return PADDING.repeat(pad - indent) + node;
    }).join('\r\n');
}

@theo-armour
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@grubersjoe

ES6 variant works for me. Thanks!

@nasermirzaei89
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nasermirzaei89 commented Mar 25, 2018 •
edited
Loading

@grubersjoe
js lint fails with this message:

Unnecessary escape character: \/ no-useless-escape

so I used [^/] in last node.match function

@MagedSaeed
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MagedSaeed commented Apr 21, 2018 •
edited
Loading

Many Thanks,, works perfect!!

@vsix27
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vsix27 commented Jun 11, 2018

did you try script on bad formed xml like

      <feed xmlns="http://www.w3.org/2005/Atom"
need="urgent">   <title type="general" sub="sample">Example Feed</title>
<subtitle><![CDATA[minor subtitle <<< ]]></subtitle>
<author nn="1" order="2" case="now"><name>John Doe</name><email>johndoe@example.com</email>
 </author>    <entry><title>Atom-Powered Robots Run Amok</title>
    <link href="http://example.org/2003/12/13/atom03" />
   <id>urn:uuid:1225c695-cfb8-4ebb-aaaa-80da344efa6a</id>
  <updated>2003-12-13T18:30:02Z</updated><summary>Some text.</summary>
 </entry>      </feed>

? it does not work for me

@JoaoPortella
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@grubersjoe
Many thanks!

@ezhov-da
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@ sente
Wow, so cool, thanks!

@huangwei16800
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<simple-value><![CDATA[部门

Dept]]>

after format xml, it will be follow result, have many space char before <![CDATA

@huangwei16800
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i had try, modify ,

var reg = /(>)(<)([^!])(/*)/g;

@brunolkatz
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thanks \o

@brennanyoung
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Good work - although I must point out that it doesn't touch existing whitespace indentation, with hilarious consequences.

@nishant-dutta
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Thanks for the code.

Here's an adapted ES6 variant:

formatXml(xml) {
    const PADDING = ' '.repeat(2); // set desired indent size here
    const reg = /(>)(<)(\/*)/g;
    let pad = 0;

    xml = xml.replace(reg, '$1\r\n$2$3');

    return xml.split('\r\n').map((node, index) => {
        let indent = 0;
        if (node.match(/.+<\/\w[^>]*>$/)) {
            indent = 0;
        } else if (node.match(/^<\/\w/) && pad > 0) {
            pad -= 1;
        } else if (node.match(/^<\w[^>]*[^\/]>.*$/)) {
            indent = 1;
        } else {
            indent = 0;
        }

        pad += indent;

        return PADDING.repeat(pad - indent) + node;
    }).join('\r\n');
}

Thanks for the ES6 version @grubersjoe ,a small addition though for handling newlines and existing whitespace between tags(as pointed out by @brennanyoung):

formatXml(xml) {
// Remove all the newlines and then remove all the spaces between tags
xml = xml.replace(/(\r\n|\n|\r)/gm, " ").replace(/>\s+</g,'><');

  const PADDING = ' '.repeat(4); // set desired indent size here
  const reg = /(>)(<)(\/*)/g;
  let pad = 0;

  xml = xml.replace(reg, '$1\r\n$2$3');

  return xml.split('\r\n').map((node, index) => {
      let indent = 0;
      if (node.match(/.+<\/\w[^>]*>$/)) {
          indent = 0;
      } else if (node.match(/^<\/\w/) && pad > 0) {
          pad -= 1;
      } else if (node.match(/^<\w[^>]*[^\/]>.*$/)) {
          indent = 1;
      } else {
          indent = 0;
      }

      pad += indent;

      return PADDING.repeat(pad - indent) + node;
  }).join('\r\n');

}

@ppazos
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ppazos commented Jul 27, 2020

I'm not sure if the latest versions of FF added more constraints, I'm getting "Toot much recursion" from formatXml()

@davidgolding
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davidgolding commented Nov 13, 2023 •
edited
Loading

A slight mismatch in one of the regular expressions needs to be: node.match(/^<[\w^>]*[^\/]>.*$/)). Merging everyone's updates, here's what I've been using:

/**
 * Prettifies the tab indentation of given XML string
 *
 * @param xml string - The XML to clean
 * @return string - Prettified XML string
 */
static prettify(xml: String) {
    let pad = 0;
    const padding = '\u0020'.repeat(4); // set desired indent size here
    
    xml = xml.replace(/(\r\n|\n|\r)/gm, '\u0020').replace(/>\s+</g,'><');
    xml = xml.replace(/(>)(<)(\/*)/g, '$1\r\n$2$3');
    
    return xml.split('\r\n').map((node, index) => { //XML elements now split into lines
        let indent = 0;
        if (node.match(/.+<\/\w[^>]*>$/)) {
            indent = 0;
        } else if (node.match(/^<\/\w/) && pad > 0) {
            pad -= 1;
        } else if (node.match(/^<[\w^>]*[^\/]>.*$/)) {
            indent = 1;
        } else {
            indent = 0;
        }
        pad += indent;
        return padding.repeat(pad - indent) + node;
    }).join('\r\n');
}

@thetilliwilli
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jlyk: if (node.match(/.+<\/\w[^>]*>$/)) { - this is extremely slow on big rows.
not for production use for sure ;) - DannyDainton/newman-reporter-htmlextra#428 (comment)

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