Rails 无法正确解码来自 jQuery 的 JSON(数组变成带有整数键的散列)

In case someone stumbles upon this and wants a better solution, you can specify the "contentType: 'application/json'" option in the .ajax call and have Rails properly parse the JSON object without garbling it into integer-keyed hashes with all-string values.

So, to summarize, my problem was that this:

$.ajax({
  type : "POST",
  url :  'http://localhost:3001/plugin/bulk_import/',
  dataType: 'json',
  data : {"shared_items": [{"entity_id":"253","position":1}, {"entity_id":"823","position":2}]}
});

导致Rails解析如下内容:

Parameters: {"shared_items"=>{"0"=>{"entity_id"=>"253", "position"=>"1"}, "1"=>{"entity_id"=>"823", "position"=>"2"}}}

whereas this (NOTE: we're now stringifying the javascript object and specifying a content type, so rails will know how to parse our string):

$.ajax({
  type : "POST",
  url :  'http://localhost:3001/plugin/bulk_import/',
  dataType: 'json',
  contentType: 'application/json',
  data : JSON.stringify({"shared_items": [{"entity_id":"253","position":1}, {"entity_id":"823","position":2}]})
});

results in a nice object in Rails:

Parameters: {"shared_items"=>[{"entity_id"=>"253", "position"=>1}, {"entity_id"=>"823", "position"=>2}]}

This works for me in Rails 3, on Ruby 1.9.3.