MapXtreme2004代码 在地图上新增加点图元

private void Button1_Click(object sender, System.EventArgs e)

{

//在当前地图中心的X和Y坐标的二分之一处画点

Map map1=MapControl1.Map;

double x=map1.Center.x/2;

double y=map1.Center.y/2;

showPointOnSearchTableMap(x,y);

}

private void showPointOnSearchTableMap(double x, double y)

{

Map map=MapControl1.Map;

MapInfo.Data.Table table=MapInfo.Engine.Session.Current.Catalog.GetTable("temp");

CoordSys coordSys=map.GetDisplayCoordSys();

if (table==null)

{

TableInfoMemTable tableInfo=new TableInfoMemTable("temp");

tableInfo.Temporary =true;

Column column;

column=new GeometryColumn(coordSys);

column.Alias="MI_Geometry";

column.DataType =MIDbType.FeatureGeometry;

tableInfo.Columns.Add(column);

column=new Column();

column.Alias="MI_Style";

column.DataType =MIDbType.Style;

tableInfo.Columns.Add(column);

table = MapInfo.Engine.Session.Current.Catalog.CreateTable(tableInfo);

}

else

{

MIConnection conn=new MIConnection();

MICommand tempcmd=conn.CreateCommand();

tempcmd.CommandText ="delete from temp";

conn.Open();

tempcmd.ExecuteNonQuery();

conn.Close();

tempcmd.Dispose();

}

//创建点及其样式

FeatureGeometry geometry=new MapInfo.Geometry.Point (coordSys,x,y);

SimpleVectorPointStyle vStyle=new SimpleVectorPointStyle(40,System.Drawing.Color.Green,14);

//创建的点的样式、颜色和大小都在上条语句中修改

CompositeStyle cStyle=new MapInfo.Styles.CompositeStyle(vStyle);

MIConnection connection=new MIConnection();

MICommand cmd=connection.CreateCommand();

cmd.Parameters.Add("geometry",MIDbType.FeatureGeometry);

cmd.Parameters.Add("style",MIDbType.Style);

cmd.CommandText ="Insert Into temp(MI_Geometry,MI_Style) values (geometry,style)";

connection.Open();

cmd.Parameters[0].Value =geometry;

cmd.Parameters[1].Value =cStyle;

int nchanged=cmd.ExecuteNonQuery();

cmd.Dispose();

//创建图层并将其插入到当前地图的最上层

FeatureLayer fl = new FeatureLayer(table);

map.Layers.Insert(0,fl);

map.Center = new MapInfo.Geometry.DPoint(x,y);

}