WKBFeatureSetsCS - sindizzy/DSW GitHub Wiki

FeatureSets from Well Known Binary

FeatureSets exist in two basic "Modes". In one mode, they are "indexed" which implies there is a single large vertex array and a series of "ShapeIndices" that let you cycle through those vertices. The second mode is to simply have multiple Features in a Feature list, and it becomes necessary to cycle through the coordinates of the geometries in order to do anything with the shapes. Opening a shapefile automatically opens it into the indexed mode, while creating a new shapefile automatically assumes that you want to work with the features list. For importing from WKB there are two strategies.

{{ ///

/// Testing for errors in X, Y coordinate positioning by saving using the /// Net Topology Suite version, while opening using the WkbFeatureReader. /// private void DuplicateShapes(object sender, EventArgs e) { // Prompt the user for a shapefile. var layer = App.Map.AddFeatureLayer(); 
// Open the featureset using standard shapefile format
IFeatureSet fs = FeatureSet.Open(layer.DataSet.Filename);

// The output featureset to be created from wkb
FeatureSet result = new FeatureSet(fs.FeatureType);

// Store the WKB representation in a list of arrays, each shape has one array.
List<byte[]()()> binaryShapes = new List<byte[]()()>();

// This forces the creation of features, and uses the old WKB converter
// which was the NTS implementation of the standard OGC WKB.
foreach (IFeature feature in fs.Features)
{
    binaryShapes.Add(feature.ToBinary());
}

// Start by setting up a list of shapes
List<Shape> shapes = new List<Shape>();

// Loop through the binary arrays
foreach (byte[]() rawBytes in binaryShapes)
{
    // read each 
    MemoryStream ms = new MemoryStream(rawBytes);
    shapes.Add(WkbFeatureReader.ReadShape(ms));
}

// As of the most recent source commit, this also works if it is false.
result.IndexMode = true;
// Adds the shapes to the result in one pass, so that there is less array re-dimensioning
result.AddShapes(shapes);
// opens the result as a new layer on the map
App.Map.Layers.Add(result);

} }}

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