$.param($.deparam('foo[10000000]=bar')); // breaks the world

[brian-gates]

See the subject. I'm not sure if this is really a bug, per se, but it's certainly an unintuitive problem.

In my particular situation I'm working with a form that has a key that represents a very high-value incremental id in the database. Serializing it provides a string not unlike the value in the subject.

The problem starts here:
$.deparam('foo[10000000]=bar'); // [undefined, undefined, undefined, 9999998 more...]

Converting this data back to a string will break the browser.

Working with objects would resolve this problem:

$.deparam('foo[10000000]=bar'); // { foo: {'1000': 'bar'} }

Not sure if this has any other functional implications, however.

[Gamesh]

i have the same problem, when merging hash with key value like 123 the hash put in the url is many undefined parameters up to 122 hashes.
ex.: param[123]=1
if pushed creates 122 param with value undefined, and the last one is our param[123]=1

[jordoh]

I just ran into the same issue with Rails' query string output for a hash with a numerical key and an array as the associated value. Passing hash[100][]=val to deparam with a numerical key would result in { hash: [ <100 nil entries>, "val" ] }.

I was able to work around it by pre-processing the params string so hash[1][]=a becomes hash['1'][]=a, which produces the desired { hash: { '1': [ "a" ] } }. Here's a bit of code that could be adapted to work without the empty brackets Rails adds:

var prepareParams = function(params) {
  return params.replace(/\[(\d+)\]\[\]=/ig, function(match, key) {
    return "['" + key + "'][]=";
  });
};

var params = $.deparam.querystring(prepareParams(window.location.href));