Edit in JSFiddle

var params = {
    pStr   : 'hoge',
    pAry   : [ 1, 2, 3 ],
    pAryObj: [ { a: 'bc', d: 'ef' }, { a: 'gh' } ]
};

echo(params);

function echo(obj) {
    var serialized = decodeURIComponent($.param(obj).replace(/&/g, '&\n'));
    $('#console').html(serialized);
}