Why is Everyone Choosing JSON Over XML for jQuery? [closed]

Answer 1

One major advantage other than the ones mentioned here. For the same data, there are multiple ways to represent it as a XML file but only one way with JSON, removes ambiguity :)

Answer 2

XML doesn't really begin to shine until you start mixing together different namespaced schemas. Then you see JSON start to fall down, but if you just need a serialization format for your data, JSON is smaller, lighterweight, more human readable, and generally faster than XML.

Answer 3

 <colors>
      <color name='red'     value='#f00'/>
      <color name='green'   value='#0f0'/>
      <color name='blue'    value='#00f'/>
      <color name='cyan'    value='#0ff'/>
      <color name='magenta' value='#f0f'/>
      <color name='yellow'  value='#ff0'/>
      <color name='black'   value='#000'/>
 </colors>

With attributes, XML is nice. But for some reason, home-made XML is generally 100% made of elements, and ugly.

Answer 4

JSON has no impedance-mismatch with JavaScript programming. JSON can contain integers, strings, lists, arrays. XML is just elements and nodes that need to be parsed into integers and so on before it can be consumed.

Answer 5

JSON is effectively serialized JavaScript in that you can eval(aJsonString) directly into a JavaScript object. Inside of a browser it's a no-brainer JSON is perfectly suited for JavaScript. At the same time JavaScript is a very loosely-typed dynamic language and cannot natively take advantage of all the specific type information available contained within an Xml/Xsd document. This extra metadata (which is great for interoperability) is a hinderance in JavaScript making it more tedious and cubersome to work with.

Size vs Performance

If you're in a browser JSON is faster to serialize/deserialize as it's simpler, more compact and more importantly natively supported. I have some northwind database benchmarks available comparing the size and speed between the different serializers available. In the Base Class Library Microsoft's XML DataContract serializer is over 30% faster than their JSON one. Although this has more to do with the effort Microsoft put into their XML serializer as I was able to develop a JsonSerializer that is more than 2.6x faster than their XML one. As for payloads based on the benchmarks it looks as though XML is roughly more than 2x the size of JSON. However this can quickly blow out if your XML payload uses many different namespaces within the same document.

Answer 6

No one here has mentioned XML-s main advantage: validation rules (DTD, XSD). My conclusions, having used both:

• JSON is perfect for ajax, especially if you develop both server and client side yourself. You basically create js objects right in your server script!
• XML shines in corporate environments, when you have to set data exchange standards between big bureaucratic organizations. Often, one party develops its part months before another, so it really benefits from validating its requests against agreed XSD. Also, in big corporations, data transfer is often translated between different systems. This is also XML's strength, think XSLT. Example: code-free conversion into JSON :p

Of course, there's json-schema being developed but you won't find built-in support for it anywhere.

I'm a fanboy of both, they have just different strengths.