Possible to pass multiple level data array using the data field of jQuery $.ajax?

How do I pass multiple level array using jQuery ajax function?

Example of data to be passed:

{"d开发者_开发知识库ata": { "username" : "name1" , "password" : "password1" } }

in

bodyContent = $.ajax({
      url: "somepage",
      global: false,
      type: "POST",
      **data:** ,
      ...

use $.param()

var params = {
    "data": {
        "username" : "name1" ,
        "password" : "password1" 
    } 
};
    var str = jQuery.param(params);
    // decodeURIComponent(str) == data[username]=name1&data[password]=password1​

here's a demo

Encode it as a JSON string.