I have to show on a gmap control in c # more markers to make use of the code below.

The strange thing is that if I display only one marker is displayed correctly, while if I have more than one marker they are not displayed correctly ie the position is wrong ! How can I solve?

C: Code:

 private void buttonCarica_Click(object sender, EventArgs e)
            if (comboBoxUtenti.Text != "")
                MapControlRisorse.MapProvider = GMapProviders.GoogleMap;

                Utente utemp = new Utente(comboBoxUtenti.Text);
                MarcaTempo tm = new MarcaTempo(utemp);
                DataTable dt = tm.CaricaRisorsa(dateTimePickerDataRisorse.Value.Date);
                if (dt.Rows.Count == 0)
                    MessageBox.Show("\n ATTENZIONE:  " + dateTimePickerDataRisorse.Value.Date);
                    //int conta = 0;
                    GMapOverlay markersOverlay = new GMapOverlay("markers");
                    foreach (DataRow dr in dt.Rows)
                        Double lat = Convert.ToDouble(dr["Latitudine"].ToString());
                        Double lon = Convert.ToDouble(dr["Longitudine"].ToString());
                        MessageBox.Show("Lat: " + lat + " \n Lon: " + lon);
                        MapControlRisorse.Position = new GMap.NET.PointLatLng(lat, lon);
                        GMarkerGoogle marker = null;
                        GMarkerGoogleType markerType = new GMarkerGoogleType();
                        var point = new GMap.NET.PointLatLng(lat, lon);

                        //Verifico se l'utente ha segnato un ingresso o un uscita
                        //Se è entrato il marker sarà verde se è uscito sarà rosso
                        if (dr["Stato"].ToString() == "Ingresso")
                            markerType = GMarkerGoogleType.green;
                            // MapControlRisorse.Overlays.Add(markersOverlay);
                        else if (dr["Stato"].ToString() == "Uscita")
                            markerType = GMarkerGoogleType.red;

                            // MapControlRisorse.Overlays.Add(markersOverlay);
                        marker = new GMarkerGoogle(point, markerType);
                        marker.ToolTipText = "" + dr["Utente"].ToString();

                    MapControlRisorse.MinZoom = 5;
                    MapControlRisorse.MaxZoom = 100;
                    MapControlRisorse.Zoom = 7;
                    MapControlRisorse.MouseWheelZoomEnabled = true;

Image of Location:

enter code here

  • how are they in the wrong place? all together in a corner? slightly offset from each other? strangely attracted to each other? maybe you could add a image showing what's going on. – Ian Turton Jun 29 '18 at 10:46
  • I posted a picture cordinate I confirm that they are right: my cordinate are these (Italy) Lat: 44.49381 Lon: 11.33875, but apparently displayed in the Indian Ocean @IanTurton – riki Jun 29 '18 at 12:14

It looks like that point is at (44,11) rather than (11,44)

enter image description here

So I would suggest changing

var point = new GMap.NET.PointLatLng(lat, lon);


var point = new GMap.NET.PointLatLng(lon, lat);

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