Thinking in GIS

   <appSettings>
    <!--  Path to MapFile -->
    <add key="mapFilePath" 
         value = "C:\training\mapServerTutorial\data\csharptutorial.map"
    />
    <add key="postgreSQLConnectionString"
         value = "Server=127.0.0.1;Port=5432;User Id=psqluser;password=psqluser;Database=TUTORIAL;"
    />
  </appSettings>

                /// <summary>
		/// Add a point feature to point shapefile with an array of values for dbf, or add a point and attributes to a point PostGIS feature class
		/// </summary>
		/// <param name="x">x image coordinate</param>
		/// <param name="y">y image coordinate</param>
		/// <param name="activeLayer">name of the active layer</param>
		/// <param name="fieldValues">array with field names and values</param>
		private void AddPoint(Double x, Double y, String activeLayer, String[,] fieldValues)
		{
      //check if the active layer is a point layer and if the point layer is from a shapefile or from PostGIS
      layerObj layer = map.getLayerByName(activeLayer);
      if(layer.type!=MS_LAYER_TYPE.MS_LAYER_POINT)
      {
        //notify action
        lblInfo.Text = "This action can be performed only on point layers.";
        return;
      }
      //convert the image point in map point
      pointObj point = pixel2point(new pointObj(x,y,0,0)); 
      //generate the sql INSERT statment
      //get field list and value list to use in the query on dbf
      String fieldList = "";
      String valueList = "";
      for(int i=0; i<(fieldValues.Length/2); i++)
      {
        fieldList = fieldList + fieldValues[i,0];
        valueList = valueList + "'" + fieldValues[i,1] + "'";
        if(i<((fieldValues.Length/2)-1))
        {
          fieldList = fieldList + ", ";
          valueList = valueList + ", ";
        }
      }
      //add the point to a shapefile
      if(layer.connectiontype==MS_CONNECTION_TYPE.MS_SHAPEFILE)
      {
        String shapeFullPath = map.shapepath + "\\" + activeLayer + ".shp";
        shapefileObj shapefile = new shapefileObj(shapeFullPath,-2);
        /*Alternative way to insert a point in the shapefile using shapeObj:
        //create line to store the point
        lineObj line = new lineObj();
        line.add(point);
        //create shape
        shapeObj shape = new shapeObj((int)MS_SHAPE_TYPE.MS_SHAPE_POINT);
        shape.add(line);
        //add shape to shapefile
        shapefile.add(shape);
        */
        shapefile.addPoint(point);
        //add record for dbf table
        String sqlInsert = "INSERT INTO " + activeLayer + " (" + fieldList + ") VALUES(" + valueList + ")";
        OleDbConnection cn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + map.shapepath + ";Extended Properties=dBASE IV;User ID=Admin;Password=");
        cn.Open();
        OleDbCommand com = cn.CreateCommand();
        com.CommandText = sqlInsert;
        com.CommandType = CommandType.Text;
        com.ExecuteNonQuery();
        cn.Close();
        shapefile.Dispose();
      }
      //add the point to a PostGIS table
      if(layer.connectiontype==MS_CONNECTION_TYPE.MS_POSTGIS)
      {
        //set CurrentCulture according to PostgreSQL server
        CultureInfo newCultureInfo = new CultureInfo("en-US");
        newCultureInfo.NumberFormat.NaNSymbol = "";
        Thread.CurrentThread.CurrentCulture = newCultureInfo;
        //connect with PostgreSQL
        //the sqlInsert includes also the geometry (with shapefile we need to make 2 different steps)
        String sqlInsert = "INSERT INTO " + activeLayer + " (" + fieldList + ",the_geom) VALUES(" + valueList + ", GeomFromText('POINT(" + point.x.ToString() + " " + point.y.ToString() + ")',-1))";
        //reads connection string for PostgreSQL
        String connectionString = System.Configuration.ConfigurationSettings.AppSettings["postgreSQLConnectionString"].ToString();
        Npgsql.NpgsqlConnection cn = new Npgsql.NpgsqlConnection(connectionString);
        cn.Open();
        Npgsql.NpgsqlCommand com = cn.CreateCommand();
        com.CommandText = sqlInsert;
        com.ExecuteNonQuery();
        cn.Close();
      }
      //notify action
      lblInfo.Text = "Point added to " + activeLayer + " point layer.";
		}

		/// <summary>
		/// Restore the original point shapefile or delete all the records from the PostGIS layer
		/// </summary>
		/// <param name="sender"></param>
		/// <param name="e"></param>
		private void butClear_Click(object sender, System.EventArgs e)
		{
			String shapeFullPath = map.shapepath + "\\" + ddlLayers.SelectedItem.Text + ".shp";
			layerObj layer = map.getLayerByName(ddlLayers.SelectedItem.Text);
      //action allowed only for point layer
      if(layer.type!=MS_LAYER_TYPE.MS_LAYER_POINT)
      {
        //notify action
        lblInfo.Text = "This action can be performed only on point layers.";
        return;
      }
      //different delete action if layer is shapefile or PostGIS
      //shapefile layer
			if(layer.connectiontype==MS_CONNECTION_TYPE.MS_SHAPEFILE)
			{
				//Clear the point shapefile by restoring its copy
				//Create a DirectoryInfo object representing the specified directory.
				DirectoryInfo dir = new DirectoryInfo(map.shapepath);
				//Get the FileInfo objects for every file that belongs to shapefile in the directory.
				FileInfo[] files = dir.GetFiles(ddlLayers.SelectedItem.Text + "Copy.*");
				for(int i=0; i<files.Length; i++)
				{
					//be sure to put a copy of the point shapefile under shapepath, the copy should be called as NameCopy (ie: for POI of this tutorial, we put a shapefile copy called POICopy)
					File.Copy(files[i].FullName, map.shapepath + "\\" + ddlLayers.SelectedItem.Text + files[i].Extension, true);
				}
				//notify action
				lblInfo.Text = "Shapefile cleared.";
			}
      //PostGIS layer
      if(layer.connectiontype==MS_CONNECTION_TYPE.MS_POSTGIS)
      {
        String connectionString = "Server=127.0.0.1;Port=5432;User Id=psqluser;password=psqluser;Database=TUTORIAL;";
        Npgsql.NpgsqlConnection cn = new Npgsql.NpgsqlConnection(connectionString);
        cn.Open();
        Npgsql.NpgsqlCommand com = cn.CreateCommand();
        com.CommandText = "DELETE FROM " + ddlLayers.SelectedItem.Text;
        com.ExecuteNonQuery();
        cn.Close();
        //notify action
        lblInfo.Text = "PostGIS layer cleared.";
      }
			ibMap.ImageUrl = "MapStream.aspx?ACTION=LAYERDELETE";
		}