if (!data) return ""; // Always return a string

var pairs = []; // To hold name=value pairs

for(var name in data) { // For each name

if (!data.hasOwnProperty(name)) continue; // Skip inherited

if (typeof data[name] === "function") continue; // Skip methods

var value = data[name].toString(); // Value as string

name = encodeURIComponent(name.replace(" ", "+")); // Encode name

value = encodeURIComponent(value.replace(" ", "+")); // Encode value

pairs.push(name + "=" + value); // Remember name=value pair

}

return pairs.join('&'); // Return joined pairs separated with &