mapxtreme 鹰眼图的开发

http://www.blogjava.net/TiGERTiAN/archive/2008/02/25/181988.html

 

很久没写blog了，备份一下，这段代码是我从网上看来的，根据需要修改了一下。

/**//// <summary>
/// 更新鹰眼图
/// </summary>
private void UpdateEyeMap()
{
try {
//如果主图和鹰眼图加载的是同一实例，那么鹰眼图就需要检测是否有效
//if (eyeMap != null)
{
//加载鹰眼矩形临时表
                    Table tblRect;
                    tblRect = Session.Current.Catalog.GetTable("TempRect");
if (tblRect != null)
                        tblRect.Close();
                    TableInfo tblInfo;
                    tblInfo = TableInfoFactory.CreateTemp("TempRect");
                    TableSessionInfo tblSessionInfo = new TableSessionInfo();

                    tblRect = Session.Current.Catalog.CreateTable(tblInfo, tblSessionInfo);
                    FeatureLayer feaLayer = new FeatureLayer(tblRect);
                    eyeMap.Layers.Insert(0, feaLayer);

//实时在鹰眼临时表图上画矩形
                    tblRect = Session.Current.Catalog.GetTable("TempRect");
                    (tblRect as ITableFeatureCollection).Clear();//清除当前层上的图元

//设置矩形的样式
                    DRect rect = mapControl.Map.Bounds;
                    FeatureGeometry feageo = new MapInfo.Geometry.Rectangle(mapControl.Map.GetDisplayCoordSys(), rect);
                    SimpleLineStyle simLineStyle = new SimpleLineStyle(new LineWidth(2, MapInfo.Styles.LineWidthUnit.Point), 2, System.Drawing.Color.Red);
                    SimpleInterior simInterior = new SimpleInterior(9, System.Drawing.Color.Gray, System.Drawing.Color.Green, true);
                    CompositeStyle comStyle = new CompositeStyle(new AreaStyle(simLineStyle, simInterior), null, null, null);

//将矩形插入到图层中
                    Feature fea = new Feature(feageo, comStyle);
                    tblRect.InsertFeature(fea);
//重新定位鹰眼图的中心
                    eyeMap.Center = map.Center;
                    eyeMap.Layers["TempRect"].Invalidate();

//清理对象变量
                    tblSessionInfo = null;
                    feageo = null;
                    simLineStyle = null;
                    simInterior = null;
                    comStyle = null;
                    fea = null;
                }
            }catch(Exception ex) {
                GlobalHelper.ShowError("显示鹰眼图错误，"+ex.Message);
            }


        }

将该函数放入Map_ViewChangedEvent事件中，每当主图改变的时候鹰眼图会跟着变化，不过速度慢了点，因为需要重绘方框和移动中心坐标。
当然之前你要载入和主图一样的地图：

//鹰眼图加载，添加不同实例，减小耦合性
                eyeMap.Load(new MapGeosetLoader(basePath + GlobalHelper.IniFile["GST"]["gstFile"]));