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Create new features and add into shapefiles?

#1

 


Edgar,


I have a point shapfile and a polygon shapfile. The shapefiles have columns of ID and Label. Then I load them into a map control.


Would you show me some sample code that can do:


(1) Create a point feature (say PointShape)  based on screen point (world location); Assign values to ID and Label columns; Save the feature into the point shapefile.


(2) Create a polygon feature based on two PointShape  points; Assign values to ID and Label columns; Save the feature into the point shapefile.


So I can reload the new created features into map control next time.


Thank you and have a nice weekend,


Mengbo



 


 



#2

Hi Mengbo,


Here is the code,



//======================== Add point feature ==================================================================
            PointShape currentPoint = new PointShape(-100, 34);// e.WorldLocation;

            ShapeFileFeatureLayer pointLayer = new ShapeFileFeatureLayer("your point shape file", ShapeFileReadWriteMode.ReadWrite);
            pointLayer.Open();

            Collection<FeatureSourceColumn> columns = pointLayer.FeatureSource.GetColumns();

            pointLayer.FeatureSource.BeginTransaction();
            Feature newFeature = new Feature(currentPoint);

            newFeature.ColumnValues.Add("LabelColumn", "New place");

            pointLayer.FeatureSource.AddFeature(newFeature);

            pointLayer.FeatureSource.CommitTransaction();
            pointLayer.FeatureSource.Close();

            winformsMap1.Refresh();

            //======================== Add polygon feature ==================================================================
            PointShape point1 = new PointShape(-100, 34);
            PointShape point2 = new PointShape(-101, 35);
            double minx = Math.Min(point1.X,point1.X);
            double miny = Math.Min(point1.Y,point1.Y);
            double maxx = Math.Max(point1.X,point1.X);
            double maxy = Math.Max(point1.Y,point1.Y);
            RectangleShape rectanglePolygon = new RectangleShape(minx, maxy, maxx, miny);
            PolygonShape currentPolygon = rectanglePolygon.ToPolygon();

            ShapeFileFeatureLayer polygonLayer = new ShapeFileFeatureLayer("your polygon shape file", ShapeFileReadWriteMode.ReadWrite);
            polygonLayer.Open();

            Collection<FeatureSourceColumn> polygonColumns = polygonLayer.FeatureSource.GetColumns();

            polygonLayer.FeatureSource.BeginTransaction();
            Feature newPolygonFeature = new Feature(currentPolygon);
            newPolygonFeature.ColumnValues.Add("LabelColumn", "New place");
            polygonLayer.FeatureSource.AddFeature(newPolygonFeature);

            polygonLayer.FeatureSource.CommitTransaction();
            polygonLayer.FeatureSource.Close();

            winformsMap1.Refresh();


Hope it helps,


Edgar



#3

Edgar,


Your sample code is very helpful. My evaluation moves well. So far verything looks postive.


Thank you very much,


Mengbo


 



#4

You’re welcome, if you have any questions please let us know. 
  
 Regards, 
 Edgar