Hashes

Converting all form elements into a Hash $H(e)

Create a form with an id attribute, then input fields as normal, with names.

The form elements must have a name attribute (id not required).

Hash to JSON:

The quick and dirty: onclick="$('hash_to_json').update($H($('form_name').serialize(true)).toJSON());"

The detailed steps:

1. Seralize the form:

   var hash_form = $('form_name').serialize(true);

2. The element type of hash_form is a JavaScript Hash, not a Prototype Hash (see gotcha below), although you *can* run some Object functions on it:
   • var json = Object.toJSON(hash_form); // Returns a JSON string

   But it doesn't behave as expected, so don't rely on Object:

   • var bool_is_hash = Object.isHash(hash_form); // returns false

   Use $H(element_name) to access it as a Prototype Hash.

3. Convert the Hash to a JSON string:

   var h = $H(hash_form);

   var json = h.toJSON();

Debugging

var hash_foo = new Hash();
hash_foo.set('name', 'Sample hash');
hash_foo.set('int', 12);

Output:

Get the contents of a hash file:

$H(hash_foo).inspect(); // returns #<Hash:{'name': 'Sample hash'}>

inspect() is prefixed by a # and enclosed in < > so it won't be displayed properly if you are just viewing HTML. It's going to be simpler to just dump it to a JSON string and display it that way.

$H(hash_foo).toJSON(); // returns {"name": "Sample hash"}

Serializing Form Gotchas

Form with id of 'simple'.

String:

To serialize a form (get all the elements into a Hash), use $(e).serialize(true);

According to the docs, this is is a Hash object, but you cannot treat it as such. Running Hash functions on it will silently fail.

	var json_hash = $('simple').serialize(true);
	
	var json_str = $H(json_hash).toJSON(); // returns string: {"text": "Simple form text"}
	
	json_hash.set('key', 'value'); // Error: json_hash.set is not a function