+
−# The GDAL C library, OGR exception, and the Field object
+
−from django.contrib.gis.gdal.error import OGRException, OGRIndexError
+
−from django.contrib.gis.gdal.field import Field
+
−from django.contrib.gis.gdal.geometries import OGRGeometry, OGRGeomType
+
−from django.contrib.gis.gdal.srs import SpatialReference
+
−
+
−# ctypes function prototypes
+
−from django.contrib.gis.gdal.prototypes.ds import \
+
−    destroy_feature, feature_equal, get_fd_geom_type, get_feat_geom_ref, \
+
−    get_feat_name, get_feat_field_count, get_fid, get_field_defn, \
+
−    get_field_index, get_field_name
+
−from django.contrib.gis.gdal.prototypes.geom import clone_geom, get_geom_srs
+
−from django.contrib.gis.gdal.prototypes.srs import clone_srs
+
−
+
−# For more information, see the OGR C API source code:
+
−#  http://www.gdal.org/ogr/ogr__api_8h.html
+
−#
+
−# The OGR_F_* routines are relevant here.
+
−class Feature(object):
+
−    "A class that wraps an OGR Feature, needs to be instantiated from a Layer object."
+
−
+
−    #### Python 'magic' routines ####
+
−    def __init__(self, feat, fdefn):
+
−        "Initializes on the pointers for the feature and the layer definition."
+
−        self._ptr = None # Initially NULL
+
−        if not feat or not fdefn:
+
−            raise OGRException('Cannot create OGR Feature, invalid pointer given.')
+
−        self._ptr = feat
+
−        self._fdefn = fdefn
+
−
+
−    def __del__(self):
+
−        "Releases a reference to this object."
+
−        if self._ptr: destroy_feature(self._ptr)
+
−
+
−    def __getitem__(self, index):
+
−        """
+
−        Gets the Field object at the specified index, which may be either
+
−        an integer or the Field's string label.  Note that the Field object
+
−        is not the field's _value_ -- use the `get` method instead to 
+
−        retrieve the value (e.g. an integer) instead of a Field instance.
+
−        """
+
−        if isinstance(index, basestring):
+
−            i = self.index(index)
+
−        else:
+
−            if index < 0 or index > self.num_fields:
+
−                raise OGRIndexError('index out of range')
+
−            i = index
+
−        return Field(self._ptr, i)
+
−    
+
−    def __iter__(self):
+
−        "Iterates over each field in the Feature."
+
−        for i in xrange(self.num_fields):
+
−            yield self[i]
+
−
+
−    def __len__(self):
+
−        "Returns the count of fields in this feature."
+
−        return self.num_fields
+
−        
+
−    def __str__(self):
+
−        "The string name of the feature."
+
−        return 'Feature FID %d in Layer<%s>' % (self.fid, self.layer_name)
+
−
+
−    def __eq__(self, other):
+
−        "Does equivalence testing on the features."
+
−        return bool(feature_equal(self._ptr, other._ptr))
+
−
+
−    #### Feature Properties ####
+
−    @property
+
−    def fid(self):
+
−        "Returns the feature identifier."
+
−        return get_fid(self._ptr)
+
−        
+
−    @property
+
−    def layer_name(self):
+
−        "Returns the name of the layer for the feature."
+
−        return get_feat_name(self._fdefn)
+
−
+
−    @property
+
−    def num_fields(self):
+
−        "Returns the number of fields in the Feature."
+
−        return get_feat_field_count(self._ptr)
+
−
+
−    @property
+
−    def fields(self):
+
−        "Returns a list of fields in the Feature."
+
−        return [get_field_name(get_field_defn(self._fdefn, i)) 
+
−                for i in xrange(self.num_fields)]
+
−
+
−    @property
+
−    def geom(self):
+
−        "Returns the OGR Geometry for this Feature."
+
−        # Retrieving the geometry pointer for the feature.
+
−        geom_ptr = get_feat_geom_ref(self._ptr)
+
−        return OGRGeometry(clone_geom(geom_ptr))
+
−
+
−    @property
+
−    def geom_type(self):
+
−        "Returns the OGR Geometry Type for this Feture."
+
−        return OGRGeomType(get_fd_geom_type(self._fdefn))
+
−    
+
−    #### Feature Methods ####
+
−    def get(self, field):
+
−        """
+
−        Returns the value of the field, instead of an instance of the Field
+
−        object.  May take a string of the field name or a Field object as
+
−        parameters.
+
−        """
+
−        field_name = getattr(field, 'name', field)
+
−        return self[field_name].value
+
−
+
−    def index(self, field_name):
+
−        "Returns the index of the given field name."
+
−        i = get_field_index(self._ptr, field_name)
+
−        if i < 0: raise OGRIndexError('invalid OFT field name given: "%s"' % field_name)
+
−        return i