public static async Task <Flight> ReadFlight(this StorageFile file)
{
using (var stream = await file.OpenStreamForReadAsync())
{
return(FlightDataReader.Read(stream));
}
}
public void Test1()
{
using (var stream = File.OpenRead("Test.json"))
{
var data = FlightDataReader.Read(stream);
}
}
private static void Subscribe(int domainId, int sampleCount)
{
// --- Create participant --- //
DDS.DomainParticipant participant =
DDS.DomainParticipantFactory.get_instance().create_participant(
domainId,
DDS.DomainParticipantFactory.PARTICIPANT_QOS_DEFAULT,
null /* listener */,
DDS.StatusMask.STATUS_MASK_NONE);
if (participant == null)
{
Shutdown(participant);
throw new Exception("create_participant error");
}
// --- Create subscriber --- //
DDS.Subscriber subscriber = participant.create_subscriber(
DDS.DomainParticipant.SUBSCRIBER_QOS_DEFAULT,
null /* listener */,
DDS.StatusMask.STATUS_MASK_NONE);
if (subscriber == null)
{
Shutdown(participant);
throw new ApplicationException("create_subscriber error");
}
// --- Create topic --- //
// Register the type before creating the topic.
string typeName = FlightTypeSupport.get_type_name();
try {
FlightTypeSupport.register_type(participant, typeName);
}
catch (DDS.Exception e) {
Console.WriteLine("register_type error {0}", e);
Shutdown(participant);
throw e;
}
DDS.Topic topic = participant.create_topic(
"Example Flight",
typeName,
DDS.DomainParticipant.TOPIC_QOS_DEFAULT,
null /* listener */,
DDS.StatusMask.STATUS_MASK_NONE);
if (topic == null)
{
Shutdown(participant);
throw new ApplicationException("create_topic error");
}
// --- Create reader --- //
DDS.DataReader reader = subscriber.create_datareader(
topic,
DDS.Subscriber.DATAREADER_QOS_DEFAULT,
null,
DDS.StatusMask.STATUS_MASK_ALL);
if (reader == null)
{
Shutdown(participant);
throw new ApplicationException("create_datareader error");
}
FlightDataReader flightReader = (FlightDataReader)reader;
// Query for company named 'CompanyA' and for flights in cruise
// (about 30,000ft). The company parameter will be changed in
// run-time. NOTE: There must be single-quotes in the query
// parameters around-any strings! The single-quote do NOT go in the
// query condition itself.
DDS.StringSeq queryParameters = new DDS.StringSeq();
queryParameters.ensure_length(2, 2);
queryParameters.set_at(0, "'CompanyA'");
queryParameters.set_at(1, "30000");
Console.WriteLine(
"Setting parameters to company: {0} and altitude >= {1}\n",
queryParameters.get_at(0), queryParameters.get_at(1));
// Create the query condition with an expession to MATCH the id
// field in the structure and a numeric comparison.
DDS.QueryCondition queryCondition =
reader.create_querycondition(
DDS.SampleStateKind.ANY_SAMPLE_STATE,
DDS.ViewStateKind.ANY_VIEW_STATE,
DDS.InstanceStateKind.ALIVE_INSTANCE_STATE,
"company MATCH %0 AND altitude >= %1",
queryParameters);
// --- Wait for data --- //
const int receivePeriod = 1000; // Milliseconds
bool update = false;
for (int count = 0;
(sampleCount == 0) || (count < sampleCount);
count++)
{
// Poll for new samples every second.
System.Threading.Thread.Sleep(receivePeriod);
// Change the filter parameter after 5 seconds.
if ((count + 1) % 10 == 5)
{
queryParameters.set_at(0, "'CompanyB'");
update = true;
}
else if ((count + 1) % 10 == 0)
{
queryParameters.set_at(0, "'CompanyA'");
update = true;
}
// Set new parameters.
if (update)
{
Console.WriteLine("Changing parameter to {0}",
queryParameters.get_at(0));
queryCondition.set_query_parameters(queryParameters);
update = false;
}
// Iterate through the samples using read_w_condition.
FlightSeq dataSeq = new FlightSeq();
DDS.SampleInfoSeq infoSeq = new DDS.SampleInfoSeq();
try {
flightReader.read_w_condition(
dataSeq,
infoSeq,
DDS.ResourceLimitsQosPolicy.LENGTH_UNLIMITED,
queryCondition);
} catch (DDS.Retcode_NoData) {
continue;
} catch (DDS.Exception e) {
Shutdown(participant);
throw e;
}
for (int i = 0; i < dataSeq.length; i++)
{
DDS.SampleInfo info = (DDS.SampleInfo)infoSeq.get_at(i);
if (info.valid_data)
{
Flight flight_info = (Flight)dataSeq.get_at(i);
Console.WriteLine(
"\t[trackId: {0}, company: {1}, altitude: {2}]\n",
flight_info.trackId,
flight_info.company,
flight_info.altitude);
}
}
try {
flightReader.return_loan(dataSeq, infoSeq);
} catch (DDS.Exception e) {
Console.WriteLine("return loan error {0}", e);
}
}
// Delete all entities
Shutdown(participant);
}
