XML escape function in Javascript.

xml_encode.js

// original:
//  - http://stackoverflow.com/questions/7918868/how-to-escape-xml-entities-in-javascript
//  - http://stackoverflow.com/questions/1091945/where-can-i-get-a-list-of-the-xml-document-escape-characters
//  - http://www.w3.org/TR/xml/#syntax

if (!String.prototype.encodeXML) {
  String.prototype.encodeXML = function () {
    return this.replace(/&/g, '&')
               .replace(/</g, '&lt;')
               .replace(/>/g, '&gt;')
               .replace(/'/g, '&apos;')
               .replace(/"/g, '&quot;');
  };
}

this will only replace the first occurrence of the chareacter. Better way to do this this.replace(new RegExp(search, 'g'), replacement); or this.split(search).join(replacement);

It would also escape the "&" characters of already escaped characters, such as: '& amp ;'.