QgsJsonUtils Class Reference

Helper utilities for working with JSON and GeoJSON conversions. More...

#include <qgsjsonutils.h>

Static Public Member Functions
static Q_INVOKABLE QString	encodeValue (const QVariant &value)
	Encodes a value to a JSON string representation, adding appropriate quotations and escaping where required.
static QString	exportAttributes (const QgsFeature &feature, QgsVectorLayer *layer=nullptr, const QVector< QVariant > &attributeWidgetCaches=QVector< QVariant >())
	Exports all attributes from a QgsFeature as a JSON map type.
static json	exportAttributesToJsonObject (const QgsFeature &feature, QgsVectorLayer *layer=nullptr, const QVector< QVariant > &attributeWidgetCaches=QVector< QVariant >())
	Exports all attributes from a QgsFeature as a json object.
static json	jsonFromVariant (const QVariant &v)
	Converts a QVariant v to a json object.
static Q_INVOKABLE QVariantList	parseArray (const QString &json, QVariant::Type type=QVariant::Invalid)
	Parse a simple array (depth=1)
static QVariant	parseJson (const QString &jsonString)
	Converts JSON jsonString to a QVariant, in case of parsing error an invalid QVariant is returned.
static QVariant	parseJson (const std::string &jsonString)
	Converts JSON jsonString to a QVariant, in case of parsing error an invalid QVariant is returned and an error is logged to the message log.
static QVariant	parseJson (const std::string &jsonString, QString &error)
	Converts JSON jsonString to a QVariant, in case of parsing error an invalid QVariant is returned and the error argument is populated accordingly.
static QgsFeatureList	stringToFeatureList (const QString &string, const QgsFields &fields=QgsFields(), QTextCodec *encoding=nullptr)
	Attempts to parse a GeoJSON string to a collection of features.
static QgsFields	stringToFields (const QString &string, QTextCodec *encoding=nullptr)
	Attempts to retrieve the fields from a GeoJSON string representing a collection of features.

Detailed Description

Helper utilities for working with JSON and GeoJSON conversions.

Since

QGIS 2.16

Definition at line 299 of file qgsjsonutils.h.

Member Function Documentation

encodeValue()

QString QgsJsonUtils::encodeValue ( const QVariant &  value )

static

Encodes a value to a JSON string representation, adding appropriate quotations and escaping where required.

Parameters

value

value to encode

Returns

encoded value

Definition at line 276 of file qgsjsonutils.cpp.

exportAttributes()

QString QgsJsonUtils::exportAttributes ( const QgsFeature &  feature, QgsVectorLayer *  layer = nullptr, const QVector< QVariant > &  attributeWidgetCaches = QVector<QVariant>()  )

static

Exports all attributes from a QgsFeature as a JSON map type.

Parameters

feature	feature to export
layer	optional associated vector layer. If specified, this allows richer export utilising settings like the layer's fields widget configuration.
attributeWidgetCaches	optional widget configuration cache. Can be used to speed up exporting the attributes for multiple features from the same layer.

Definition at line 313 of file qgsjsonutils.cpp.

exportAttributesToJsonObject()

json QgsJsonUtils::exportAttributesToJsonObject ( const QgsFeature &  feature, QgsVectorLayer *  layer = nullptr, const QVector< QVariant > &  attributeWidgetCaches = QVector<QVariant>()  )

static

Exports all attributes from a QgsFeature as a json object.

Parameters

feature	feature to export
layer	optional associated vector layer. If specified, this allows richer export utilising settings like the layer's fields widget configuration.
attributeWidgetCaches	optional widget configuration cache. Can be used to speed up exporting the attributes for multiple features from the same layer.

Note

Not available in Python bindings

Since

QGIS 3.8

Definition at line 561 of file qgsjsonutils.cpp.

jsonFromVariant()

json QgsJsonUtils::jsonFromVariant ( const QVariant &  v )

static

Converts a QVariant v to a json object.

Note

Not available in Python bindings

Since

QGIS 3.8

Definition at line 406 of file qgsjsonutils.cpp.

parseArray()

QVariantList QgsJsonUtils::parseArray ( const QString &  json, QVariant::Type  type = QVariant::Invalid  )

static

Parse a simple array (depth=1)

Parameters

json	the JSON to parse
type	optional variant type of the elements, if specified (and not Invalid), the array items will be converted to the type, and discarded if the conversion is not possible.

Since

QGIS 3.0

Definition at line 337 of file qgsjsonutils.cpp.

parseJson() [1/3]

QVariant QgsJsonUtils::parseJson ( const QString &  jsonString )

static

Converts JSON jsonString to a QVariant, in case of parsing error an invalid QVariant is returned.

Note

Not available in Python bindings

Since

QGIS 3.8

Definition at line 556 of file qgsjsonutils.cpp.

parseJson() [2/3]

QVariant QgsJsonUtils::parseJson ( const std::string &  jsonString )

static

Converts JSON jsonString to a QVariant, in case of parsing error an invalid QVariant is returned and an error is logged to the message log.

Note

Not available in Python bindings

Since

QGIS 3.8

Definition at line 461 of file qgsjsonutils.cpp.

parseJson() [3/3]

QVariant QgsJsonUtils::parseJson ( const std::string &  jsonString, QString &  error  )

static

Converts JSON jsonString to a QVariant, in case of parsing error an invalid QVariant is returned and the error argument is populated accordingly.

Note

Not available in Python bindings

Since

QGIS 3.24

Definition at line 474 of file qgsjsonutils.cpp.

stringToFeatureList()

QgsFeatureList QgsJsonUtils::stringToFeatureList ( const QString &  string, const QgsFields &  fields = QgsFields(), QTextCodec *  encoding = nullptr  )

static

Attempts to parse a GeoJSON string to a collection of features.

It is possible to specify fields to parse specific fields, if not provided, no fields will be included. An encoding can be specified which defaults to UTF-8 if it is nullptr.

Returns

a list of parsed features, or an empty list if no features could be parsed

See also

stringToFields()

Note

this function is a wrapper around QgsOgrUtils::stringToFeatureList()

Definition at line 260 of file qgsjsonutils.cpp.

stringToFields()

QgsFields QgsJsonUtils::stringToFields ( const QString &  string, QTextCodec *  encoding = nullptr  )

static

Attempts to retrieve the fields from a GeoJSON string representing a collection of features.

An encoding can be specified which defaults to UTF-8 if it is nullptr.

Returns

retrieved fields collection, or an empty list if no fields could be determined from the string

See also

stringToFeatureList()

Note

this function is a wrapper around QgsOgrUtils::stringToFields()

Definition at line 268 of file qgsjsonutils.cpp.

---

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

• /build/qgis-3.34.0+99sid/src/core/qgsjsonutils.h
• /build/qgis-3.34.0+99sid/src/core/qgsjsonutils.cpp