This is a modified version of JSON in JavaScript which adds an option to pretty print the JSON output.

Download: JSON-js-prettyPrint (js, 5 KB)

  object.toJSONString(prettyPrint)
  array.toJSONString(prettyPrint)
    prettyPrint ... if set to true the resulting string will be formated
                    with tabs and returns to be more human readable.

Here is an example data object:

   var data = {
      "eins" : "Eins",
      "int" : 2,
      "number" : 2.234,
      "obj" : {
         "a" : "A", b:"B", c:"C"
      },
      "array" : ["eins","zwei","drei",{"vier":4,"null":null,"undefined":undefined},{"vier":4,"null":null,"undefined":undefined},"zwei","drei",{"vier":4,"null":null,"undefined":undefined}],
      isBoolean : true
   };

data.toJSONString() will ouput:

{"array":["eins","zwei","drei",{"vier":4,"null":null},{"vier":4,"null":null},"zwei","drei",{"vier":4,"null":null}],"eins":"Eins","obj":{"a":"A","b":"B","c":"C"},"number":2.234,"isBoolean":true,"int":2}

data.toJSONString(true) will ouput:

{
	"array" : [
		"eins",
		"zwei",
		"drei",
		{
			"vier" : 4,
			"null" : null
		},
		{
			"vier" : 4,
			"null" : null
		},
		"zwei",
		"drei",
		{
			"vier" : 4,
			"null" : null
		}
	],
	"eins" : "Eins",
	"obj" : {
		"a" : "A",
		"b" : "B",
		"c" : "C"
	},
	"number" : 2.234,
	"isBoolean" : true,
	"int" : 2
}

why i did it?
on the client side it doesn't seem to make sense to pretty print the JSON output, because in most cases you will send it back to a server. but we use the script on the server side (using Helma/Rhino) so it makes perfectly sense for us.