public string GetLocations()
{
var list = _manager.GetGpsItems();
Guid id = Guid.Parse("80dd122e-1418-4965-8f14-245005804d0a");
//SetPosition(id);
string url = "http://www.gps902.net/api/GetMonitor.aspx?ids=356803210132270,353507000002012,353507100003389&mapType=baidu&key=20161222HLXTJDMW730XY";
string json = Common.HttpHelper.Get(url);
return(Common.Utils.SerializeObject(list));
}