Winform下的地图开发控件(GMap.NET)使用心得之二

在上篇《下的开发(GMap.NET)使用心得》中简单介绍了GMap.NET的控件基本情况，本篇开始介绍一下相关的代码操作。

其实目前GMap.NET提供的功能还不是很多，因此其演示的例子基本上都涉及到了，我在此基础上做了一些改进和运用，总结下功能代码吧。

首先使用控件前，需要初始化一些变量和事件，初始化代码如下所示：

代码

         private void InitMapControl()
        {
             this .gMapControl1.Manager.Mode = AccessMode.ServerAndCache;
             this .gMapControl1.MapType = MapType.GoogleMapChina;
             this .gMapControl1.MaxZoom = 18 ;
             this .gMapControl1.MinZoom = 8 ;
             this .gMapControl1.Zoom = 13 ;

             this .gMapControl1.MouseMove += new MouseEventHandler(gMapControl1_MouseMove);
             this .gMapControl1.DoubleClick += new EventHandler(gMapControl1_DoubleClick);
             this .gMapControl1.MouseDown += new MouseEventHandler( this .MainMap_MouseDown);
             this .gMapControl1.MouseUp += new MouseEventHandler( this .MainMap_MouseUp);

             this .gMapControl1.OnCurrentPositionChanged += new CurrentPositionChanged( this .MainMap_OnCurrentPositionChanged);
             this .gMapControl1.OnTileLoadStart += new TileLoadStart( this .MainMap_OnTileLoadStart);
             this .gMapControl1.OnTileLoadComplete += new TileLoadComplete( this .MainMap_OnTileLoadComplete);

             this .gMapControl1.OnMarkerClick += new MarkerClick( this .MainMap_OnMarkerClick);
             this .gMapControl1.OnMapZoomChanged += new MapZoomChanged( this .MainMap_OnMapZoomChanged);
             this .gMapControl1.OnMapTypeChanged += new MapTypeChanged( this .MainMap_OnMapTypeChanged);

             this .routes = new GMapOverlay( this .gMapControl1, " routes " );
             this .gMapControl1.Overlays.Add( this .routes);
             this .objects = new GMapOverlay( this .gMapControl1, " objects " );
             this .gMapControl1.Overlays.Add( this .objects);
             this .top = new GMapOverlay( this .gMapControl1, " top " );
             this .gMapControl1.Overlays.Add( this .top);
             this .currentMarker = new GMapMarkerGoogleRed( this .gMapControl1.CurrentPosition);
             this .top.Markers.Add( this .currentMarker);
             this .center = new GMapMarkerCross( this .gMapControl1.CurrentPosition);
             this .top.Markers.Add( this .center);

             this .myShop = new GMapOverlay( this .gMapControl1, " myShop " );
             this .gMapControl1.Overlays.Add( this .myShop);
            DisplayMyShop();

            SetZoomCenter();

             this .gMapControl1.DragButton = MouseButtons.Left;
        }

其中的OnMarkerClick好像虽然有相关的事件，但是并不能捕获单击图标的时间操作，估计是没有完成该功能吧。

GMap.NET提供了各种鼠标的操作事件，我们重载即可实现特殊的控制处理了：

鼠标事件操作

         void gMapControl1_DoubleClick( object sender, EventArgs e)
        {
             this .gMapControl1.Zoom += 1 ;
             this .gMapControl1.CurrentPosition = lastPosition;
        }

         void gMapControl1_MouseMove( object sender, MouseEventArgs e)
        {
            PointLatLng latLng = this .gMapControl1.FromLocalToLatLng(e.X, e.Y);
             this .tsslPosition.Text = string .Format( " 经度：{0}, 纬度：{1} " , latLng.Lng, latLng.Lat);
        }

         private void MainMap_MouseDown( object sender, MouseEventArgs e)
        {
             if (e.Button == MouseButtons.Left)
            {
                 this .isMouseDown = true ;
                lastPosition = this .gMapControl1.FromLocalToLatLng(e.X, e.Y);
            }
        }

         private void MainMap_MouseUp( object sender, MouseEventArgs e)
        {
             if (e.Button == MouseButtons.Left)
            {
                 this .isMouseDown = false ;
            }
        }

保存截图的操作如下所示

代码

         private void tsbSavePicture_Click( object sender, EventArgs e)
        {
             try
            {
                 using (SaveFileDialog dialog = new SaveFileDialog())
                {
                    dialog.Filter = " PNG (*.png)|*.png " ;
                    dialog.FileName = " GMap.NET image " ;
                    Image image = this .gMapControl1.ToImage();
                     if (image != null )
                    {
                         using (image)
                        {
                             if (dialog.ShowDialog() == DialogResult.OK)
                            {
                                 string fileName = dialog.FileName;
                                 if ( ! fileName.EndsWith( " .png " , StringComparison.OrdinalIgnoreCase))
                                {
                                    fileName += " .png " ;
                                }
                                image.Save(fileName);
                                MessageBox.Show( " 图片已保存： " + dialog.FileName, " GMap.NET " , MessageBoxButtons.OK, MessageBoxIcon.Asterisk);
                            }
                        }
                    }
                }
            }
             catch (Exception exception)
            {
                MessageBox.Show( " 图片保存失败： " + exception.Message, " GMap.NET " , MessageBoxButtons.OK, MessageBoxIcon.Hand);
            }

地址查询并绘制图标的代码如下：

代码

private void btnSearch_Click( object sender, EventArgs e)
        {
             if ( this .txtAddress.Text.Length == 0 )
            {
                 this .txtAddress.Focus();
                MessageBox.Show( " 请输入查询的地址 " );
            }

             string search = string .Format( " {0},{1} " , this .txtCity.Text, this .txtAddress.Text);
            GeoCoderStatusCode code = this .gMapControl1.SetCurrentPositionByKeywords(search);
             if (code != GeoCoderStatusCode.G_GEO_SUCCESS)
            {
                MessageBox.Show( " 地址没有找到：' " + this .txtAddress.Text + " ', 原因： " + code.ToString(), " GMap.NET " , MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
            }

             this .objects.Markers.Clear();
            AddLocation( this .txtAddress.Text);
        }

         private void AddLocation( string place)
        {
            GeoCoderStatusCode unknow = GeoCoderStatusCode.Unknow;
            PointLatLng ? latLngFromGeocoder = Singleton < GMaps > .Instance.GetLatLngFromGeocoder(place, out unknow);
             if (latLngFromGeocoder.HasValue && (unknow == GeoCoderStatusCode.G_GEO_SUCCESS))
            {
                GMapMarker item = new GMapMarkerGoogleGreen(latLngFromGeocoder.Value);
                GMapMarkerRect rect = new GMapMarkerRect(latLngFromGeocoder.Value);
                rect.Size = new System.Drawing.Size( 100 , 100 );
                rect.ToolTipText = place;
                rect.TooltipMode = MarkerTooltipMode.Always;
                 this .objects.Markers.Add(item);
                 this .objects.Markers.Add(rect);
            }
        }

绘制两地之间的线路图命令如下所示：

代码

         private void ctxMenu_GetRout_Click( object sender, EventArgs e)
        {
             this .objects.Markers.Clear();
             this .routes.Routes.Clear(); // 清楚路线

             this .start = defaultLocation;
             this .end = this .gMapControl1.FromLocalToLatLng( this .contextMenuStrip1.Bounds.X, this .contextMenuStrip1.Bounds.Y);

            MapRoute route = Singleton < GMaps > .Instance.GetRouteBetweenPoints( this .start, this .end, false , ( int ) this .gMapControl1.Zoom);
             if (route != null )
            {
                GMapRoute item = new GMapRoute(route.Points, route.Name);
                item.Color = Color.Blue;
                 this .routes.Routes.Add(item);

                GMapMarker marker = new GMapMarkerGoogleRed( this .start);
                 // marker.ToolTipText = "Start: " + route.Name;
                marker.TooltipMode = MarkerTooltipMode.Always;

                 // Placemark place = this.gMapControl1.Manager.GetPlacemarkFromGeocoder(this.end); // 地标不准确，不用
                MapRoute mapRoute = this .gMapControl1.Manager.GetRouteBetweenPoints( this .start, this .end, true , ( int ) this .gMapControl1.Zoom);
                GMapMarker marker2 = new GMapMarkerGoogleGreen( this .end);
                marker2.ToolTipText = string .Format( " 目的地距离:{0}公里 " , Math.Round(mapRoute.Distance, 2 ));
                marker2.TooltipMode = MarkerTooltipMode.Always;

                 this .objects.Markers.Add(marker);
                 this .objects.Markers.Add(marker2);
                 this .gMapControl1.ZoomAndCenterRoute(item);
            }
        }

放大、缩小、重新加载地图的操作如下：

代码

         private void ctxMenu_ZoomOut_Click( object sender, EventArgs e)
        {
             this .gMapControl1.Zoom += 1 ;
        }

         private void ctxMenu_ZoomIn_Click( object sender, EventArgs e)
        {
             this .gMapControl1.Zoom -= 1 ;
        }

         private void tsbReload_Click( object sender, EventArgs e)
        {
             this .gMapControl1.ReloadMap();
        }

程序截图如下所示：

转载请注明本文地址： Winform下的地图开发控件(GMap.NET)使用心得之二

Winform下的地图开发控件(GMap.NET)使用心得之二

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