The feature class encapsulates a single feature including its id, geometry and a list of field/values attributes. More...

#include <qgsfeature.h>

Public Member Functions
	QgsFeature (QgsFeatureId id=QgsFeatureId())
	Constructor.
	QgsFeature (const QgsFields &fields, QgsFeatureId id=QgsFeatureId())
	QgsFeature (const QgsFeature &rhs)
	copy ctor needed due to internal pointer
	~QgsFeature ()
	Destructor.
QVariant	attribute (const QString &name) const
	Lookup attribute value from attribute name.
QVariant	attribute (int fieldIdx) const
	Lookup attribute value from its index.
const QgsAttributes &	attributes () const
QgsAttributes &	attributes ()
void	deleteAttribute (int field)
	Deletes an attribute and its value.
bool	deleteAttribute (const QString &name)
	Remove an attribute value.
int	fieldNameIndex (const QString &fieldName) const
	Utility method to get attribute index from name.
const QgsFields *	fields () const
	Get associated field map.
QgsGeometry *	geometry () const
	Get the geometry object associated with this feature.
QgsGeometry *	geometryAndOwnership ()
	Get the geometry object associated with this feature The caller assumes responsibility for the QgsGeometry*'s destruction.
QgsFeatureId	id () const
	Get the feature id for this feature.
void	initAttributes (int fieldCount)
	Initialize this feature with the given number of fields.
bool	isValid () const
	Return the validity of this feature.
QgsFeature &	operator= (QgsFeature const &rhs)
	assignment operator needed due to internal pointer
bool	setAttribute (int field, const QVariant &attr)
	Set an attribute by id.
bool	setAttribute (const QString &name, QVariant value)
	Insert a value into attribute.
void	setAttributes (const QgsAttributes &attrs)
void	setFeatureId (QgsFeatureId id)
	Set the feature id for this feature.
void	setFields (const QgsFields *fields, bool initAttributes=false)
	Assign a field map with the feature to allow attribute access by attribute name.
void	setGeometry (const QgsGeometry &geom)
	Set this feature's geometry from another QgsGeometry object (deep copy)
void	setGeometry (QgsGeometry *geom)
	Set this feature's geometry (takes geometry ownership)
void	setGeometryAndOwnership (unsigned char *geom, size_t length)
	Set this feature's geometry from WKB.
void	setValid (bool validity)
	Set the validity of the feature.

Detailed Description

The feature class encapsulates a single feature including its id, geometry and a list of field/values attributes.

Encapsulates a spatial feature with attributes.

Author: Gary E.Sherman

Definition at line 113 of file qgsfeature.h.

Constructor & Destructor Documentation

QgsFeature::QgsFeature ( QgsFeatureId id = QgsFeatureId() )

Constructor.

Definition at line 27 of file qgsfeature.cpp.

QgsFeature::QgsFeature	(	const QgsFields &	fields,
		QgsFeatureId	id = `QgsFeatureId()`
	)

Definition at line 36 of file qgsfeature.cpp.

QgsFeature::QgsFeature ( const QgsFeature & rhs )

copy ctor needed due to internal pointer

Definition at line 46 of file qgsfeature.cpp.

QgsFeature::~QgsFeature ( )

Destructor.

Definition at line 89 of file qgsfeature.cpp.

Member Function Documentation

QVariant QgsFeature::attribute ( const QString & name ) const

Lookup attribute value from attribute name.

Returns invalid variant if attribute name could not be converted to index (C++ only) Field map must be associated to make this work.

Parameters

name	The name of the attribute to get

Returns: The value of the attribute (C++: Invalid variant if no such name exists )

Note: For Python: raises a KeyError exception if field is not found

Definition at line 230 of file qgsfeature.cpp.

QVariant QgsFeature::attribute ( int fieldIdx ) const

Lookup attribute value from its index.

Returns invalid variant if the index does not exist.

Parameters

fieldIdx The index of the attribute to get

Returns: The value of the attribute (C++: Invalid variant if no such index exists )

Note: For Python: raises a KeyError exception if field is not found

Definition at line 222 of file qgsfeature.cpp.

const QgsAttributes& QgsFeature::attributes ( ) const

inline

Definition at line 142 of file qgsfeature.h.

QgsAttributes& QgsFeature::attributes ( )

inline

Definition at line 143 of file qgsfeature.h.

void QgsFeature::deleteAttribute ( int field )

Deletes an attribute and its value.

Parameters

field The index of the field

Note: For Python: raises a KeyError exception if the field is not found

Definition at line 106 of file qgsfeature.cpp.

bool QgsFeature::deleteAttribute ( const QString & name )

Remove an attribute value.

Returns false if attribute name could not be converted to index. Field map must be associated to make this work.

Parameters

name	The name of the field to delete

Returns: false if attribute name could not be converted to index (C++ only)

Note: For Python: raises a KeyError exception instead of returning false

Definition at line 212 of file qgsfeature.cpp.

int QgsFeature::fieldNameIndex ( const QString & fieldName ) const

Utility method to get attribute index from name.

Returns -1 if field does not exist or field map is not associated. Field map must be associated to make this work.

Definition at line 239 of file qgsfeature.cpp.

const QgsFields* QgsFeature::fields ( ) const

inline

Get associated field map.

TODO: QGIS 3 - return reference or value, not pointer

Definition at line 231 of file qgsfeature.h.

QgsGeometry * QgsFeature::geometry ( ) const

Get the geometry object associated with this feature.

Definition at line 112 of file qgsfeature.cpp.

QgsGeometry * QgsFeature::geometryAndOwnership ( )

Get the geometry object associated with this feature The caller assumes responsibility for the QgsGeometry*'s destruction.

Definition at line 117 of file qgsfeature.cpp.

QgsFeatureId QgsFeature::id ( ) const

Get the feature id for this feature.

Returns: Feature id

Definition at line 100 of file qgsfeature.cpp.

void QgsFeature::initAttributes ( int fieldCount )

Initialize this feature with the given number of fields.

Discard any previously set attribute data.

Parameters

fieldCount Number of fields to initialize

Definition at line 181 of file qgsfeature.cpp.

bool QgsFeature::isValid ( ) const

Return the validity of this feature.

This is normally set by the provider to indicate some problem that makes the feature invalid or to indicate a null feature.

Definition at line 171 of file qgsfeature.cpp.

QgsFeature & QgsFeature::operator= ( QgsFeature const & rhs )

assignment operator needed due to internal pointer

Definition at line 63 of file qgsfeature.cpp.

bool QgsFeature::setAttribute	(	int	field,
		const QVariant &	attr
	)

Set an attribute by id.

Parameters

field	The index of the field to set
attr	The value of the attribute

Returns: false, if the field id does not exist

Note: For Python: raises a KeyError exception instead of returning false

Definition at line 190 of file qgsfeature.cpp.

bool QgsFeature::setAttribute	(	const QString &	name,
		QVariant	value
	)

Insert a value into attribute.

Returns false if attribute name could not be converted to index. Field map must be associated to make this work.

Parameters

name	The name of the field to set
value	The value to set

Returns: false if attribute name could not be converted to index (C++ only)

Note: For Python: raises a KeyError exception instead of returning false

Definition at line 202 of file qgsfeature.cpp.

void QgsFeature::setAttributes ( const QgsAttributes & attrs )

inline

Definition at line 144 of file qgsfeature.h.

void QgsFeature::setFeatureId ( QgsFeatureId id )

Set the feature id for this feature.

Set the feature id.

Parameters

id	Feature id

Definition at line 128 of file qgsfeature.cpp.

void QgsFeature::setFields	(	const QgsFields *	fields,
		bool	initAttributes = `false`
	)

Assign a field map with the feature to allow attribute access by attribute name.

Parameters

fields	The attribute fields which this feature holds. When used from python, make sure a copy of the fields is held by python, as ownership stays there. I.e. Do not call feature.setFields( myDataProvider.fields() ) but instead call myFields = myDataProvider.fields() feature.setFields( myFields )
initAttributes	If true, attributes are initialized. Clears any data previously assigned. C++: Defaults to false Python: Defaults to true

TODO: QGIS3 - take reference, not pointer

Definition at line 161 of file qgsfeature.cpp.

void QgsFeature::setGeometry ( const QgsGeometry & geom )

Set this feature's geometry from another QgsGeometry object (deep copy)

Definition at line 134 of file qgsfeature.cpp.

void QgsFeature::setGeometry ( QgsGeometry * geom )

Set this feature's geometry (takes geometry ownership)

Note: not available in python bindings

Definition at line 139 of file qgsfeature.cpp.

void QgsFeature::setGeometryAndOwnership	(	unsigned char *	geom,
		size_t	length
	)

Set this feature's geometry from WKB.

Set the pointer to the feature geometry.

This feature assumes responsibility for destroying geom.

Definition at line 154 of file qgsfeature.cpp.

void QgsFeature::setValid ( bool validity )

Set the validity of the feature.

Definition at line 176 of file qgsfeature.cpp.

The documentation for this class was generated from the following files:

/tmp/buildd/qgis-2.8.2+12wheezy/src/core/qgsfeature.h
/tmp/buildd/qgis-2.8.2+12wheezy/src/core/qgsfeature.cpp

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation