[C#]利用纠偏数据来处理地球坐标(WGS-84)与火星坐标 (GCJ-02)转换

关键代码：

using System;

using System.Collections;

using System.Collections.Generic;

using System.IO;

using YanZhiwei.DotNet2.Utilities.Models;

namespace YanZhiwei.DotNet2.Utilities.Common

{

    /// <summary>

    /// 地图纠偏数据帮助类

    /// </summary>

    public class MapOffsetDataHelper

    {

        #region 构造函数以及变量

        private string offsetFullPath = string.Empty;

        /// <summary>

        /// 构造函数

        /// </summary>

        /// <param name="path">纠偏数据文件路径</param>

        public MapOffsetDataHelper(string path)

        {

            offsetFullPath = path;

        }

        #endregion

        #region 私有方法

        private void GetOffsetData(Action<MapCoord> mapCoordHanlder)

        {

            using (FileStream stream = new FileStream(offsetFullPath, FileMode.OpenOrCreate, FileAccess.Read))

            {

                using (BinaryReader reader = new BinaryReader(stream))

                {

                    int _size = (int)stream.Length / 8;

                    for (int i = 0; i < _size; i++)

                    {

                        byte[] _source = reader.ReadBytes(8);

                        MapCoord _coord = ToCoord(_source);

                        mapCoordHanlder(_coord);

                    }

                }

            }

        }

        /// <summary>

        /// 将字节转化为具体的数据对象

        /// </summary>

        /// <param name="bytes">bytes</param>

        /// <returns>MapCoord</returns>

        private MapCoord ToCoord(byte[] bytes)

        {

            //经度,纬度,x偏移量,y偏移量 【均两个字节】

            MapCoord _coord = new MapCoord();

            byte[] _b1 = new byte[2], _b2 = new byte[2], _b3 = new byte[2], _b4 = new byte[2];

            Array.Copy(bytes, 0, _b1, 0, 2);

            Array.Copy(bytes, 2, _b2, 0, 2);

            Array.Copy(bytes, 4, _b3, 0, 2);

            Array.Copy(bytes, 6, _b4, 0, 2);

            _coord.Lon = BitConverter.ToInt16(_b1, 0);

            _coord.Lat = BitConverter.ToInt16(_b2, 0);

            _coord.X_off = BitConverter.ToInt16(_b3, 0);

            _coord.Y_off = BitConverter.ToInt16(_b4, 0);

            return _coord;

        }

        #endregion 

        #region 获取纠偏数据集合

        /// <summary>

        /// 获取纠偏数据集合

        /// </summary>

        /// <returns>纠偏数据集合</returns>

        public List<MapCoord> GetMapCoordList()

        {

            List<MapCoord> _mapCoordList = new List<MapCoord>();

            GetOffsetData(c => _mapCoordList.Add(c));

            return _mapCoordList;

        }

        /// <summary>

        /// 获取纠偏数据集合

        /// </summary>

        /// <returns>纠偏数据集合</returns>

        public ArrayList GetMapCoordArrayList()

        {

            ArrayList _mapCoordArrayList = new ArrayList();

            GetOffsetData(c => _mapCoordArrayList.Add(c));

            return _mapCoordArrayList;

        }

        #endregion

    }

}

-----------------------------------------------------------------------------------------------

using System.Collections;

using YanZhiwei.DotNet2.Utilities.Models;

using YanZhiwei.DotNet2.Utilities.Tool;

namespace YanZhiwei.DotNet2.Utilities.Common

{

    /// <summary>

    /// 地图纠偏 帮助类

    /// </summary>

    public class MapOffsetHelper

    {

        /*

         *参考：

         *1.http://www.apkbus.com/forum.php?mod=viewthread&tid=137621&extra=page%3D1&page=1

         *2.http://yanue.net/post-122.html

         *3.http://go2log.com/2011/08/30/%E4%B8%AD%E5%9B%BD%E5%9C%B0%E5%9B%BE%E5%81%8F%E7%A7%BB%E6%A0%A1%E6%AD%A3php%E7%AE%97%E6%B3%95/

         *4.http://www.devdiv.com/ios_gps_google_-blog-60266-10835.html

         */

        #region 构造函数以及变量

        private ArrayList mapCoordArrayList;

        /// <summary>

        /// 构造函数

        /// </summary>

        /// <param name="offsetData">纠偏数据</param>

        public MapOffsetHelper(ArrayList offsetData)

        {

            mapCoordArrayList = offsetData;

        }

        #endregion

        #region 私有方法

        private MapCoord QueryOffSetData(LatLngPoint point)

        {

            MapCoord _search = new MapCoord();

            _search.Lat = (int)(point.LatY * 100);

            _search.Lon = (int)(point.LonX * 100);

            MapOffsetComparer rc = new MapOffsetComparer();

            int _findedIndex = mapCoordArrayList.BinarySearch(0, mapCoordArrayList.Count, _search, rc);

            MapCoord _findedCoord = (MapCoord)mapCoordArrayList[_findedIndex];

            return _findedCoord;

        }

        #endregion 

        #region 地球坐标(WGS-84)转火星坐标 (GCJ-02)

        /// <summary>

        /// 地球坐标(WGS-84)转火星坐标 (GCJ-02)

        /// </summary>

        /// <param name="wgsPoint">地球坐标(WGS-84)</param>

        /// <returns>火星坐标 (GCJ-02)</returns>

        public LatLngPoint WGS84ToGCJ02(LatLngPoint wgsPoint)

        {

            MapCoord _findedCoord = QueryOffSetData(wgsPoint);

            double _pixY = MapHelper.LatToPixel(wgsPoint.LatY, 18);

            double _pixX = MapHelper.LonToPixel(wgsPoint.LonX, 18);

            _pixY += _findedCoord.Y_off;

            _pixX += _findedCoord.X_off;

            double _lat = MapHelper.PixelToLat(_pixY, 18);

            double _lng = MapHelper.PixelToLon(_pixX, 18);

            return new LatLngPoint(_lat, _lng);

        }

        #endregion

        #region 火星坐标转 (GCJ-02)地球坐标(WGS-84)

        /// <summary>

        /// 火星坐标转 (GCJ-02)地球坐标(WGS-84)

        /// </summary>

        /// <param name="gcjPoint">火星坐标转 (GCJ-02)</param>

        /// <returns>地球坐标(WGS-84)</returns>

        public LatLngPoint GCJ02ToWGS84(LatLngPoint gcjPoint)

        {

            MapCoord _findedCoord = QueryOffSetData(gcjPoint);

            double _pixY = MapHelper.LatToPixel(gcjPoint.LatY, 18);

            double _pixX = MapHelper.LonToPixel(gcjPoint.LonX, 18);

            _pixY -= _findedCoord.Y_off;

            _pixX -= _findedCoord.X_off;

            double _lat = MapHelper.PixelToLat(_pixY, 18);

            double _lng = MapHelper.PixelToLon(_pixX, 18);

            return new LatLngPoint(_lat, _lng);

        }

        #endregion

    }

}