How to build query string with Javascript

function form_params( form )
{
    var params = new Array()
    var length = form.elements.length
    for( var i = 0; i < length; i++ )
    {
    	element = form.elements[i]

    	if(element.tagName == 'TEXTAREA' )
    	{
    		params[element.name] = element.value
    	}
    	else if( element.tagName == 'INPUT' )
    	{
    		if( element.type == 'text' || element.type == 'hidden' || element.type == 'password')
    		{
    			params[element.name] = element.value
    		}
    		else if( element.type == 'radio' && element.checked )
    		{
    			if( !element.value )
    				params[element.name] = "on"
    			else
    				params[element.name] = element.value

    		}
    		else if( element.type == 'checkbox' && element.checked )
    		{
    			if( !element.value )
    				params[element.name] = "on"
    			else
    				params[element.name] = element.value
    		}
    	}
    }
    return params;
}

function serialize(form) {
  if (!form || !form.elements) return;

  var serial = [], i, j, first;
  var add = function (name, value) {
    serial.push(encodeURIComponent(name) + '=' + encodeURIComponent(value));
  }

  var elems = form.elements;
  for (i = 0; i < elems.length; i += 1, first = false) {
    if (elems[i].name.length > 0) { /* don't include unnamed elements */
      switch (elems[i].type) {
        case 'select-one': first = true;
        case 'select-multiple':
          for (j = 0; j < elems[i].options.length; j += 1)
            if (elems[i].options[j].selected) {
              add(elems[i].name, elems[i].options[j].value);
              if (first) break; /* stop searching for select-one */
            }
          break;
        case 'checkbox':
        case 'radio': if (!elems[i].checked) break; /* else continue */
        default: add(elems[i].name, elems[i].value); break;
      }
    }
  }

  return serial.join('&');
}

function buildUrl(url, parameters){
  var qs = "";
  for(var key in parameters) {
    var value = parameters[key];
    qs += encodeURIComponent(key) + "=" + encodeURIComponent(value) + "&";
  }
  if (qs.length > 0){
    qs = qs.substring(0, qs.length-1); //chop off last "&"
    url = url + "?" + qs;
  }
  return url;
}

//example:
var url = "http://www.site.com/";
var parameters = new Array();
parameters["name"] = "George Washington";
parameters["dob"] = "17320222";
alert(buildUrl(url, parameters));
//displays: http://www.site.com/?name=George%20Washington&dob=17320222

var foo = document.createElement("elementnamehere");
   foo.attribute = allUserSpecifiedDataConsideredDangerousHere;
   somenode.appendChild(foo);

document.write("<elementnamehere attribute=""
        + ilovebrokenwebsites
        + "">"
        + stringdata
        + "</elementnamehere>");

Object.toQueryString({ action: 'ship', order_id: 123, fees: ['f1', 'f2'], 'label': 'a demo' })

// -> 'action=ship&order_id=123&fees=f1&fees=f2&label=a%20demo'