WP7中关于地图开发需要用的一些定位距离计算的知识集锦

今天做个了WP7的地图的小练习，其中包括一些关机GPS根据经纬度定位，GPS距离计算，定位当前城市。翻阅了不少资料，得到了这些知识， 下面列出这些代码，供大家参考，以免在以后学习中少走弯路。。。

 

1:根据GPS获取经纬度
 private void button2_Click(object sender, RoutedEventArgs e)
        {
            GeoCoordinateWatcher watcher = new GeoCoordinateWatcher(GeoPositionAccuracy.Default);
            watcher.MovementThreshold = 20;
            watcher.PositionChanged += new EventHandler<GeoPositionChangedEventArgs<GeoCoordinate>>(watcher_PositionChanged);
            watcher.StatusChanged += new EventHandler<GeoPositionStatusChangedEventArgs>(watcher_StatusChanged);
            watcher.Start();
        }
        void watcher_StatusChanged(object sender, GeoPositionStatusChangedEventArgs e)
        {
            switch (e.Status)
            {
                case GeoPositionStatus.Initializing:
                    break;
                case GeoPositionStatus.Ready:
                    break;
                case GeoPositionStatus.NoData:
                    break;
                case GeoPositionStatus.Disabled:
                    break;
            }
        }

        void watcher_PositionChanged(object sender, GeoPositionChangedEventArgs<GeoCoordinate> e)
        {
            string[] ss = e.Position.Location.ToString().Split(',');

            //map1..Center = new GeoCoordinate(double.Parse(ss[0]), double.Parse(ss[1]));
            System.Device.Location.GeoCoordinate location = new System.Device.Location.GeoCoordinate(double.Parse(ss[0]), double.Parse(ss[1]));
            //System.Device.Location.GeoCoordinate location = new System.Device.Location.GeoCoordinate(36.40, 117.00);
            //36.40 ，东经117.00

            Pushpin pin = new Pushpin();
            pin.Location = e.Position.Location;
            this.map1.Children.Add(pin);
            this.map1.SetView(location, 10);
        }

 

2:根据城市名称获取经纬度    //需引用webSeriver服务  http://dev.virtualearth.net/webservices/v1/geocodeservice/GeocodeService.svc/mex

 private void button1_Click(object sender, RoutedEventArgs e)
        {
            GeocodeReference1.GeocodeServiceClient geocodeClient = new GeocodeReference1.GeocodeServiceClient("BasicHttpBinding_IGeocodeService");
            geocodeClient.GeocodeCompleted += new EventHandler<GeocodeReference1.GeocodeCompletedEventArgs>(geocodeClient_GeocodeCompleted);

            GeocodeReference1.GeocodeRequest request = new GeocodeReference1.GeocodeRequest();
            request.Credentials = new Credentials();
           
            //request.Credentials.ApplicationId = ((ApplicationIdCredentialsProvider)this.map1.CredentialsProvider).ApplicationId;
            request.Credentials.ApplicationId = "AjjGZGtCVs7lEuRn860kGigumg5hhJ8LqKXOIxpk1zwuxxQUgcrFDRWmrYfYCtFg";
            request.Query = "Jinan";

           
            geocodeClient.GeocodeAsync(request);
        }

        void geocodeClient_GeocodeCompleted(object sender, GeocodeReference1.GeocodeCompletedEventArgs e)
        {
            GeocodeReference1.GeocodeResult resule = e.Result.Results[0];
            double dLatitude = resule.Locations[0].Latitude;

            double dLongitude = resule.Locations[0].Longitude;

            System.Device.Location.GeoCoordinate location = new System.Device.Location.GeoCoordinate(dLatitude, dLongitude);

            Pushpin pin = new Pushpin();

            pin.Location = location;

            this.map1.Children.Add(pin);

            this.map1.SetView(location,10);

        }

 

3:得到两地区的在地图上的距离

 private const double EAETH_RADIUS = 6378.137;
        public static double rad(double d)
        {
            return d * Math.PI / 180.0;
        }
       

        public static double getDistance(double lat1, double lng1, double lat2, double lng2)
        {
            double radLat1 = rad(lat1);
            double radLat2 = rad(lat2);

            double a = radLat1 - radLat2;
            double b = rad(lng1) - rad(lng2);
            double s = 2 * Math.Asin(Math.Sqrt(Math.Pow(Math.Sin(a / 2), 2) + Math.Cos(radLat1) * Math.Cos(radLat2) * Math.Pow(Math.Sin(b / 2), 2)));
            s = s * EAETH_RADIUS;
            s = Math.Round(s * 10000) / 10000;
            return s;
        }

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            double dd = getDistance(36.40, 117.00, 39.57, 116.17);
        }

4:nokia ovi地图服务接口