private void Request_Completed(object sender, RequestEventArgs e)
{
//不做e.Error的判断
if (e.Result != null && !string.IsNullOrEmpty(e.Result))
{
GetLayersInfoResult result = GetLayersInfoResult.FromJson(e.Result);
lastResult = result;
GetLayersInfoEventArgs args = new GetLayersInfoEventArgs(result, e.Result, e.UserState);
OnProcessCompleted(args);
}
}