ruby-on-rails - Ruby on Rails : send javascript array of arrays to ruby controller

Question

我想将一个javascript数组数组发送到我的ruby Controller 。我有点迷茫。我的问题在 Controller 中。这是我到目前为止的内容:

(totalChanges是一个数组的数组。JSON.stringify(totalChanges)可能看起来像这样:

[[4,2,"","15"],[4,3,"","12"],[4,4,"","14"]]

app/views/index.html.erb:

<div id="dataTable" class="dataTable" style="width: 680px;height: 300px; overflow: scroll"></div>
<button>Save!</button>
<script>
    var first = true;
    var totalChanges = new Array();
    $("#dataTable").handsontable({
         //...some code that generates appropriate array totalChanges
    });
    var data = //..some code
    $("#dataTable").handsontable("loadData", data);
    $(function() {
            $( "button").button();
            $( "button" ).click(function() { 
                    alert("clicked"); 
                    $.ajax({
                            type: "POST",
                            url: "/qtl_table/save",
                            data: {total_changes: JSON.stringify(totalChanges)},
                            success: function() { alert("Success!"); }
                    });
            });
    });

</script>

app/controllers/qtl_table_controller.rb:

def save
  //Adding some things suggested by answers:
  logger.debug "\n#{params[:total_changes].first}, #{params[:total_changes][1]}\n"
  ar = JSON.parse(params[:total_changes])
end

我最终遇到这些错误:

NoMethodError (You have a nil object when you didn't expect it!
You might have expected an instance of Array.
The error occurred while evaluating nil.first):

编辑:我也有contentType:“应用程序/json”，并接受:“应用程序/json”，当我拿出那些都解决了。多谢你们 :)

Answer 1

JSON.parse 是您的 friend :

ar = JSON.parse(params[:total_changes])
#=> [[4, 2, "", "15"], [4, 3, "", "12"], [4, 4, "", "14"]]

您很可能需要将AJAX调用更新为以下内容:

$.ajax({
  type: "POST",
  url: "/qtl_table/save",
  data: { total_changes: JSON.stringify(totalChanges) },
  success: function() { alert("Success!"); }
});

给出您的数组参数 total_changes名称。