/**
* Create a QueryString with all the fields of this class different of Null
*
* @return the String with the param codified in the QueryString
*/
public String generateQueryString()
{
QueryString qs = new QueryString("page", this.page.ToString());
qs.add("limit", this.limit.ToString());
if (this.keyword != null) qs.add("keyword", this.keyword);
if (this.createdAtMin != default(DateTime)) qs.add("created_at_min", DateMethods.ToString(this.createdAtMin));
if (this.createdAtMax != default(DateTime)) qs.add("created_at_max", DateMethods.ToString(this.createdAtMax));
if (this.lang != null)qs.add("lang", this.lang);
if (this._slugs != null) qs.add("slug",this._slugs);
if (this._origins != null) qs.add("origin", string.Join(",", this._origins));
if (this._destinations != null) qs.add("destination", string.Join(",", this._destinations));
if (this._tags != null) qs.add("tag", string.Join(",", this._tags));
if (this._fields != null) qs.add("fields", string.Join(",",this._fields));
//globalJSON.put("tracking", trackingJSON);
return qs.getQuery();
}