将多边形形状文件转换为线形状文件

 import ogr, os

def poly2line(input_poly,output_line):

    source_ds = ogr.Open(input_poly)
    source_layer = source_ds.GetLayer()

    # polygon2geometryCollection
    geomcol =  ogr.Geometry(ogr.wkbGeometryCollection)
    for feat in source_layer:
        geom = feat.GetGeometryRef()
        ring = geom.GetGeometryRef(0)
        geomcol.AddGeometry(ring)

    # geometryCollection2shp
    shpDriver = ogr.GetDriverByName("ESRI Shapefile")
    if os.path.exists(output_line):
            shpDriver.DeleteDataSource(output_line)
    outDataSource = shpDriver.CreateDataSource(output_line)
    outLayer = outDataSource.CreateLayer(output_line, geom_type=ogr.wkbMultiLineString)
    featureDefn = outLayer.GetLayerDefn()
    outFeature = ogr.Feature(featureDefn)
    outFeature.SetGeometry(geomcol)
    outLayer.CreateFeature(outFeature)

def main(input_poly,output_line):
    poly2line(input_poly,output_line)

if __name__ == "__main__":
    input_poly = 'test_polygon.shp'
    output_line = 'test_line.shp'

    main(input_poly,output_line)