In new version of jquery, could done it via following steps:
serializeArray()
push()
or similar methods to add additional params to the array,$.param(arr)
to get serialized string, which could be used as jquery ajax's data
param.Example code:
var paramArr = $("#loginForm").serializeArray();
paramArr.push( {name:'size', value:7} );
$.post("rest/account/login", $.param(paramArr), function(result) {
// ...
}